I saw some dyno's of these cams on an otherwise stock MSP almost a decade ago...
It didn't give crazy gains (more than they do on an NA FS though)...but it did a great job of flattening out the mid range curve...it created a noticeably smoother transition between off to on boost...stock MSP's have a pretty peak mid range when the boost finally builds a little...which makes the car feel a little faster than it really is as all of a sudden there is considerable torque...but the cams will move that output a little higher up on the curve, which in a lot of cases is more useful...I didn't ride in a car with them installed, but I would assume just by the numbers it noticeably reduced lag and would DEFINITELY help with front wheel traction and torque steer on cars modified more than a stock MSP...
all i'm getting at is that they won't hurt a tubo'd car...these cams are truly not that aggressive in any direction, they simply help the head breathe a little better than it otherwise would (which is just about as bad as possible)...you don't have to have them, as you can get around the breathing problems with other modifications once turbo'd...and may end up wanting more aggressive cams in the long run...but if you want a more 'sleeper'ish' turbo'd car that is a lot more driveable with higher boost levels, these cams will help a lot...