Got one of the pre-order 32Ts. Tested it a bit, it was great, so removed the chain device too- just clutch mech and ring. Today at fort william my dh bike started making scary rattly noises so I decided to take the Ragley down the world cup route for the "one last ride"... So that's pretty much the most continuous rattling I'll ever give my hardtails, and lo, the chain stayed on- even when the rider didn't
So yeah, these magic chainring things? They're magic. Kenda Slant 6? Good for xc, less good at downhill. Northwinds? Basically idiots.