I did it on my '05 STi. Had the TGVs deleted and intake manifold ported at the same time. Can't comment on how effective porting the TB is on its own. Can't imagine it'll do much, but it won't hurt anything unless they mess it up.
Some people have swapped the throttle body to the one from a bigger toyota motor, I think the 5.7, but it didnt make much difference. There is a slight increase in throttle response, but fuel economy goes way down