id think that even a canned tune from will (overkill) would be better than just any random speed shop. there arent a whole lot of people who decide to mod a GM 3800, so not many poeple know the specifics of tuning it.

if you do end up going with a local shop, make sure they will warrenty their work just incase they blow up your car. i dont really let anyone work on my car unless i know them personally and know they will do it right. otherwise i do everything on my own.