It's the soft sidewalls that feel a little squirmy. Feeling some movement is somewhat normal as far as i'm concerned. It's very hard to say whether it's excessive or not since we're not in the car. Might just be a sensation you're not used too, but will get the feel of it over time. My concern when I brought it up earlier in the thread, was more about the transition from power to shutdown. As far as the pressure, even with the 7" rims, I doubt you should have to go much lower then 15 lbs, especially at your power level. As long as the tires are in good shape as you say, I think the suspension/weight transfer area is where i'd look for improvement first.