Seeing as you've got ITB's on TPS/MAP tuning down, I'd stick with that.
The majority of AFM's can be a fair restriction anyway. I back to back tested this with the FJ20 datto, when I got it running on the sprint 500. First run @ 19psi made 185rwkw(with the AFM plumbed but not using for tuning) then ditched it and power went to 215rwkw and everything happens 1,500-2,000rpm earlier.
It certainly wouldn't be the case for all AFM's, people seem to get good results with Z32 ones.