I stay at both Courtyards and Hampton Inns a lot. Hampton quality varies quite a bit. Stay at an older one and you might as well be at a family budget motel at half the price; stay at a newer one and you'll feel like you're getting a bargain. On the other hand, Courtyard is always a consistent product. Between that and what many feel is a slightly more generous rewards program, a lot of business travelers prefer Courtyards.
I find Courtyards often overpriced, though. Heavy business travelers book them up first, so when I'm making my plans only a few days out I frequently see rates $30-50/night over the competition. It's a good brand, and I'd book it more if it were more price competitive, but....