Terrain Textures, Alpha/Splatmap Texture Sets profiling?

I’ve read that it is best to use 1-4 textures for a Terrain, there’s a performance penalty for each ‘set of 4’ above that: even with 5 you pay the price going up to the 8th, and you pay again for the next set.

Now that Unity 5 provides the profiler, I’m curious how much this ‘performance penalty’ is for my target PC platform. I’m clicking through the profile but honestly not sure which of these stats I’m looking at is the metric I can use to compare the performance of having additional texture sets. Anyone know?

Don’t know that it’s really the answer, but the only noticeable difference I saw between having 1-4 textures and 5-8 was one or two additional SetPass calls with really no other impact.