Out of curiosity, which 3d applications have the least amount of issues with importing assets nativity or as .FBX?
Unity only imports FBX
Any other “native asset” is pushed through the application its created with invisibly to export FBX actually
so then it just depend on how when the application exports to .FBX?
Which is "best?, no idea. But I would rate Blender’s integration with Unity as “Good” to “Very Good”. Static models, UV’s and materials import fine. Rigs and skinned animations also import fine once you learn how Unity wants it (discussed before, search for past posts). There are obviously many features in Blender that do not import, nor would you expect them to (the fluid simulator for example), but one thing that does not import is simple object animations (such as object move, scale and rotate animations). With the exception of that one limitation I think the integration is nearly seamless.
Maya I feel would be the best integrated with Unity. As it is the only (Mac) 3D package that supports the for range of tools for game art creation, that also then successfully imported into Unity. Vertex baking, vertex colouring, multiple UVs, bone based animation, complex animation baking, etc, etc.
Not sure about Max or XSI, but if you have the budget then I’d go straight to Maya.
Mind you I use modo nearly 100% now with Unity and its FBX exporting is very good… but doesn’t have the range that Maya does.
Cheers.
Anything you can do in Maya for using it inside Unity can be also acomplished in Blender. Better save the money and get Unity Pro + Asset server 
Well since I have no absolute real need for a 3d modeling/animation package, I am not going to spend anything (I just want to be able to practice). I wish Maya still had PLE (damn Autodesk) but since they don’t I won’t be playing with that.
I know that people say that Blender as far as functionality is concerned is as good as the big boys like Maya but the interface is just terrible (I have used Maya when it still had the PLE and its interface was so much better). I think the interface to your tools is just as or more important than the functionality of the tool since even if the tool can do something, making someone jump through hoops to get it now does not need them any good (I mean Unity would not be nearly as attractive as it is if it say have the editor the TGEA has).
I have Blender 2.5 is suppose to have major improvement to the interface but I have not idea how long it will take till 2.5 is released, well see what happens.
What “people” say that? Sounds like you’re looking to start another “this 3D app is better than that 3D app” debate. Please don’t, just use the search button and you’ll find this has been debated ad nauseum. For people who use and like Blender, the interface is just fine. In fact, most Blender users want to make sure that in 2.5 most of what is good about Blender’s interface doesn’t change.
I’m sure if you check the forums for Maya, Max, Cinema4D, etc. etc. people who use and like those apps will have similar strong feelings about why those UI’s are superior.
So getting back to the topic you started, Blender and Maya certainly integrate well with Unity and both are available for Mac and Windows. Another contender that some people like, although it’s only available on a Mac, is Cheetah3D. I don’t use Cheetah, but have demoed it and know its developer has spent a lot of effort making it work seamlessly with Unity. Beyond that, any other 3d app that can export .FBX (if you want animations) or .OBJ files will work, perhaps not as seamlessly as the others I mentioned, but will certainly work good enough for most of us.
Well said bigkahuna,
Remember it does not matter what tools you use in your pipeline, all that matters is does it meet your needs and budget.
So if you have little or no budget the idea is to use what you can afford until such a time as you can afford what you want.
(small rant)
Or you can just sit and compare that what you can’t afford to that what you can. 
They all are until you get used to them 
That is kinda like saying TGEA world builder interface is just as easy as Untiy’s once you get used to it. now I am not saying the blenders interface is not fast and efficient once you get used to it but if you can go into an application and just do something without any experience in it easily, chances are once you really learn the interface, it will be so much more efficient than something where when you go into it and you can’t even rotate the camera view without look at docs.
Now I know this is no such thing as one interface that works for everyone but it seems like Blender’s interface is praised by the minority and complained by the majority.
See second quote
I understand your desire for easy to use IU, but when you make statements like I’m not going to spend anything and then you want to know what package has the least problems importing into Unity and you are given the available options you complain.
The reason I started with Blender is the same as yours I did not want to spend money I did not have and I felt that Autodesk and the Big game developers were just trying to keep people like me out.
But the Blender developers desire is that everyone should have the opportunity to have access to equally powerful tools for free.
How cool is that and at a time when Autodesk is just trying to make it even harder.
So I am glad for blender even if it a little harder to use.
Well just because it is free, does not give me the right to complain (just means I might not use it.
When I said I not going to spend anything should have been more like I don’t want to spend a min of 2K. I am actually currently looking on Modo and hoping they are going to have at least a little character animation functionality in 401 and that is something I am willing to spend (900) for a 3d application.
I wouldn’t know, I’ve never used TGEA.
I agree with that but except for maybe Cheeta3D and Silo I’ve never come across any 3D progs that didn’t have rather incomprehensible interfaces for beginners, especially on the high end side. In fact, for new users the higher end you go, the more features clutter up the interface and the more confusing and user-hostile it gets. That every 3D app likes to do things its own way with terminology and what-have-you doesn’t help much either. I don’t think Blender stands out much in this regard, hence my comment.
Look at Carrara 7 Pro. It is inexpensive and has FBX export.
Carrara 6 Pro is currently available on some 3D magazines (full version) for the price of the mag - so pretty darn cheap and GREAT interface.
Mike
What sort of luck have you had with Carrara’s exports to Unity? I gave up on Carrara a while back (C6Pro) because its export capability lacked a couple critical features (UV maps for one if I recall correctly). How complete is the export feature now a days with version 7?
IMO Carrara’s always had high marks in the “prettiest GUI” department, but some of its features are still sub par, for example the UV editing tools are a bit weak and it lacks a built in texture baking capability (there is the “Baker” plug in, but even that is pretty lame). I had a lot of hope that Carrara would grow into a first rate tool, but then Daz bought it and, well, that was the end of my hopes. I’d be happy to learn that all this has changed.
It’s gained 3D painting and the Collada support is reasonable - still have to figure out how to export textures.
I use Ultimate Unwrap 3D Pro for UV, but Carrara does allow for UV editing - just not sure how robust it is.
Overall, I find Carrara to be pretty stable and full featured for what I need it for thus far - but that may change with Unity if it does not work 100% for me.
Mike
Be sure to post what you learn, the topic of using Carrara with Unity comes up from time to time and it would be nice to know whether it works or not.
I probably won’t bother buying the upgrade since I’m pretty comfortable with Blender, but who knows?
If you do not have 6 pro, then look for the current 3d magazines - full version is on their cover disk.
I’d wait a few months and then you can get 7 pro for the price of a magazine when 8 pro is out, and so on.
I will probably never upgrade again - just wait for the mags to have the next version.
Daz is stupid to lose customers this way.
Mike