I have run the UTG Pro Keymod 13" and the BCM KMR-A 10" side by side on my latest builds. At first I thought the UTG had a really great mounting system, with screws going straight into the barrel nut and anti-rotation ears wrapping around the upper, and even recommended them to others... but at one point all 4 mounting screws loosened up on me and the handguard got loose and started sliding forward. I noticed it after I installed a muzzle device when I may have been torquing on the handguard some... either that or it just loosened up with normal use. Then when I went to re-tighten the screws, the heads started stripping. I wish they used a little better quality hardware. I did do a 10K Run 'n Gun with the UTG rifle after that where it got beat around a little and it held up fine. I probably just should have loc-tited the screws to begin with.
In any case, I trust my BCM handguard more. I have decided to go with another KMR-A on my latest build even though it costs somewhat more. The KMR is about $75 more than the UTG, but it does come with BCM's excellent sling mount, which is a $20 item and is something I would buy anyway for the other handguard, so it is really more like a $55 difference. That is well worth it for the extra confidence I will have in it.