I only just picked up my MS3, but i did a s*** tonne of research prior. From what I have read, the mazda engineers did an excellent job wit the TMIC and air delivery system. For me, I do not see any reason to upgrade to a new top mount, on a system that is already pretty efficient. Heat soak will always be an issue with a top mount system.
As far as the FMIC goes, there are multiple threads arguing for and against it. 1000 is a lot to drop for such a small increase in HP/TQ.
I mean, correct me if I am wrong by any means, but I feel as though the money could def be better spent i.e. fuel management, BPV, TBE. Hell, I was even considering adding a small scoop to the top of the hood for the TMIC.