A narrow wide chain ring with a clutch rear mech works really well at keeping your chain on. In a year of using such a set up I’ve been pleased apart from just three times when I lost the chain .Unfortunately this is three times too many so I got myself a chain device.
I’ve been running 1×10 drivetrains for ages now and up to the ‘narrow wide’ I always used a full chain device with top cage and bottom jockey wheel to keep the chain safely in place. Bottom rollers are a bit noisy and a bit draggy though and the jockey wheel is something else to wear out and need maintenance.
The MRP AMg chain guide is a top cage only guide for the new ‘clutch age’. It also has a stout bash plate which slides over stuff that you smash into, saving the honour of the chain ring. It’s silent as well and the bit of clear tube on the back of the cage helps here, reducing chain slap sounds. Weight is only about 120g so there’s no problem there making this a bit of a no brainer. The one fitted to my bike is for 28-34 tooth chainring (I’m running 30t). It’s very easy to fit and the instructions (it’s OK you are allowed to read them even if you’re a man) are in simple English.
Since fitting it I haven’t lost the chain which is nice and I’ve ridden some rough and rocky tracks in the Pyrenees as well as the local Hebden Bridge trails. Get one.