I converted a Sram XO 3x10 to a 2x10 back in March having been suffering with loads of chain loss. I'm now on a full Sram XO drive train (with a medium caged rear derailleur) and the MRP 2x10 chain device, which by all accounts was developed by MRP in conjunction with Sram.
Thing is every so often I am still losing my chain but not in the way you'd expect. Some how the chain is managing to get off the front jockey wheels and past the the jockey wheel cover plates and then either stays on the front ring and by passes the device or slips off onto the cranks.
It's a proper Houdini trick and I've no idea how it does it. Anybody had experience of this or got any suggestions ?