Best Performance: Tag or GetComponent + Rendering/Diactivating

Greetings everyone, i searched related topics but didnt get the answer i needed , well my problem is simple. I have 1600 exacly objects with a mesh renderer,a collider,a mesh filter and a script of my own. What i need it to make those objects not consume any performance and i created a script that does it for me now i want to know if Disactivating the whole object is equal to disabling its mesh renderer only or disabling both its mesh renderer and mesh filter. And also i want to know if its better for each one of them to have like 6 times a if(GetComponent(…).somevariable == “blahblah”) or a if (hit.trasform.tag == “blahblah”) [witch makes 9600 of these in the function update].

Using: Unity 3.5.6 pro

Thnx both of you your answers were really helpful and i really had forgotten about the profiler i think what Snake said is right , i will try with tags and if it doesnt work i will use the GetComponent function while i will keep an eye on the profiler , Thnx again for the quick help.