I've got a zee mech teamed up with a raceface narrow/wide (32 tooth). Dropped chain once in three months (yesterday grrr). I've increased the clutch tension a tad, so hoping will be alright.
Basically they are excellent. Chain retention is superb. Chain slap non existent. It's great reaching small pedally bits on descents and just knowing the chain will still be on.
It's only been three months, but so far it has been brilliant. The shifter is ace as well, much more 'gunshot' than my old slx shifters.
I am going to stick the granny ring back on for big days as my legs aren't up to the 1x10 thing on longer and hillier rides. I reckon I can cope with the shame of manually changing the front ring to have the 'get out of jail' of a granny ring when fatigue or cramp set in.
Shorter cage = less chance of twotting it on rocks as well. A good thing given that the initial change was semi enforced by a mech going into my rear wheel and bending my (integral to the frame) mech hanger!