You'd get both drivability and max power if you optimized your pcm
I can tell you my sig combo was just awful before I used a Tweecer to
make it behave like a little stocker
It surged, bucked, stalled out at lights, and would not idle at anything
less than 1200 rpm
After I got all the drivability issues half way decent I picked up a good
bit of max power with the maf transfer, spark/fuel tables
Yes you can use a Tweecer but you can use other methods as well
I would have to say ... ANYONE ... can tune their own car
Then again ... some just don't want to
They don't have the time or patience or ... what ever
I could not say if self tuning is the right thing for you
I had a lot of fun learning about the pcm and how it goes about doing
its thing and I dealt with some really cool peeps in the self tuning
community as well
Grady