Been smashing around on some Ms (1900s, not 1700) in the Lakes, rocky trail centres and Surrey Hills, and no issues. They’re just a temporary cheap replacement for crappy carbon wheels that cracked just at the sight of a small bump in a fireroad. I trust the M way more than the carbon stuff I had.
Given it’s on my 5010, lighter, shorter travel, used more for general mix of trails, XC and all mountain stuff, the M seemed better choice for bit lighter weight. If I was doing more of the heavy stuff, or I was heavier myself, I’d go E.
That said I’m really intending replacing with a custom build of XM421 or 481 with 350 hubs. I’ve also got a set of EX471 on my Nomad for the heavier stuff, which supposedly are tough as.
Only thing I’ll say about the E/M etc factory sets is they tend to come with centrelock hubs unless OEM, and check the truing. Oh, and I think they’re all straight pull?