I've had an hydorxx 20" and the frame lasted 9 months, then it broke. It was the first version of the frame.
Since 3 weeks ago I was riding a hydroxx 2 26", and it also broke. I rode her since march 2009.
Both frames didn't have any dents, they broke because of the use.
If I were you, I wouldn't go for a sky. I would go for a echo lite, an echo team, a zoo lynx or a rockman manus