I would personally not place too much faith in Dragon Orbs. They have decent cooling performance, but I've heard of fans failing a little too often for my taste.
I would say either go with one of the following choices:
ThermalRight SK6 for decent cooling in constricted spaces
Alpha 8045 for excellent cooling at a good price and a superior mounting system
SwifTech MCX-462 for absolute best air cooling (and superior mounting system)
[dave@discovery ~] kill -9 1
init: Just what do you think you're doing, Dave?