Our college is installing Xirrus right now. Just got done with testing various systems, including Aruba, Cisco, and Ruckus. Ruckus is good if you're looking for minimum users on 2.4Ghz only. Aruba and Cisco are a step up as they'll give you better performance and security on both 2.4 and 5GHz. All of these are limited though to two radio per AP.
We chose Xirrus -- these Arrays (as they call them) put several 2.4 and 5GHz radios into a single device like mobile towers. One Array is covering 90 pupils across three of our classrooms...all streaming video simultaneously.
The other guys only supported 16 users per AP -- it's simple math -- 8 video users per radio x 2 radios = 16 users. Xirrus had 8 video users per radio x 16 radios = 128 users.
Anyone telling you Ruckus spanked the big guys either goofed on the testing or is getting a kick back of some type. Numbers don't lie.