Where is the best place and places I may want to avoid when getting my car tuned? Thanks in advance!

 

C'mon guys... I know you have had good/bad experiences. I need to get my car tuned this weekend and have no idea where to go. I went to a place near Dallas that started with an "A" and I did not like their customer service nor expertise. I had to have my car reflashed by GM just so it would run decent again.


Please HELP!!!