The Ruckus R600's are my go-to. I've done several offices and retail installations with those.
A close second is Xirrus, their APs are a bit bigger is size and look like oversized smoke detectors though. Though, if you work in events they are perfect: Controller built into the unit, and they have weird configurations of radios so you can deploy 16 directional radios on one device. Great for conferences where you can setup 2 of those in the corners, turn off the radios not pointing at the guests and have total airspace supremacy.
