I've used both CVS and Walgreens. Both do well enough for me, though I'm not very particular. I stopped using CVS after I noticed that they were cutting through the negative a disturbing number of times to sleeve them. Never had a problem with Walgreens, I just wish it was cheaper. Its about $9 here to get the film processed and scanned to a CD, no prints. I feel like I should get higher resolutions scans for that price, but you can't beat it for convenience.
I'd also suggest giving them a test roll and see if you like the results, every location is going to vary.