I fixed mine with a ported throttlebody, there really is no horsepower gain, but the response is pretty good. I think it made a difference. pm me you r email info and I can put you in touch with the guy who does them.

as for firmer trans shifts, I'm also looking after that right now, I've ordered blue top solenoids from a member and will post my fidings. I have an SE (SXT) and yes there are limitations hindering it's true performance. the predator for the 2010 programming will not adjust shift firmness. This I know first hand, but I will be posting about the solenoids when I get them.