if you are running a guide there’s not much point in using a NW, might as well run an ordinary one
Mmm. I’m not running a device, but there’s still a case for belt and braces- top guide + narrow/wide should work a lot better than guide and standard single ring, and might give a bit of extra insurance for really hard use.
Having said that, it was enough of a pain in the arris to get the chain back on with my MRP 1X and a standard ring, add in a narrow/wide and I bet that’s a total nightmare (it cost me something like 3 minutes with a jammed chain in an enduro race, gutted). Whereas as mattbee says, with no chain device you can just throw it back on pretty much instantly.