This article in the Los Angeles Times discusses where to get the best rotisserie chicken in L.A. But it might be of interest to folks outside that area because it tells you a lot about what to look for in a good rotisserie chicken and those guidelines apply elsewhere.
They're partially wrong, I think, about supermarket rotisserie chix. Sometimes, you get one that's been sitting there under the heat lamps since the days they gave Green Stamps with them…but you don't have to settle for that. When you get to the market, zip over to the department that prepares the birds and ask if and when they'll have a fresh batch. At least, it always works for me at local Ralphs markets. If you don't get there too late in the day, there are usually birds coming off the turntable and they can be awfully good for an hour or so after.
The same is true with the hens you can get at Costco. For some reason, it always amazes me that Costco sells a perfectly ordinary-sized rotisserie chicken. I always feel like because it's Costco, it's going to come with about eighty drumsticks, thirty thighs and a dozen breasts.
Otherwise locally, I used to like the Zankou mini-chain but they became inconsistent about the time one of the owners decided to kill another and himself. At Hollywood and Gower, there's a place called Al Wazir that now does Zankou better than Zankou. (Zankou, for you outta-towners, offers a Mediterranean-style roaster which customers slather with a special garlic paste. When they were good, there was nothing better.)
What I really miss is a local chain called Chicken Natural that used to offer chickens cooked with nothing more than a little lemon juice. You can do a lot of interesting things to make a chicken tasty but nothing beats just cooking them fresh and simple. Wish we still had Chicken Naturals around.