I have seen some good and bad jobs. It really depends on what you are paying for. The problem with the big name shops is they have some really cheap paint specials and you will get exactly what you pay for on those.
On the other hand the corvette I currently own prior to me owning it got a $1500 dollar paint job (that was about 15 years ago). They sprayed over the dust on the inside of the mirrors the bonding of the paint is not good etc.
So my recommendation would be check with a local corvette club. Tell them what you are looking for. I assume you are looking at a daily driver paint job.
I would take everything off of the car that I could prior to it being painted or make sure that they have written down exactly what they will remove and what they will mask. I'm big on removing everything rather than masking things off. I would also go down and take a close look at some of their completed work.
That all said I have gotten bad paint jobs from good shops and have gotten good paint jobs form cheap shops.
I know this is not much help but. But the key is look at what they have done. Take a look at cars that are ready for painting and see if any are over or under masked. If they do not want you to look at their preparation walk away. By the way GM put on some good paint but crappy paint jobs on our cars in the first place.