I bought a Motec system from JG and it was screwed up. They did work on my short block and screwed it up. They won't do anything about either one (I am preparing a lawsuit against Javier right now). I would not by ANYTHING from JG.
I don't think you can expect too much from changing just your throttle body. In fact, years back, I replaced the throttle bodies on my Nissan with bigger ones and the car lost power. I think the stock NSX intake does a fine job. Try working on the exit part of the equation to pick up some needed HP.