I own both flexmeters and a pair of level halfpipes. The flexmeters absolutely have better protection, but are pretty massive, the standalone wristguards actually blew out a couple pairs of hestra gloves that I had, but worked pretty well with some dakine titans that I sized up with (usually medium in gloves, wore a large with the flexmeters.)
The flexmeter gloves that are available in the US are... frankly pretty trashy. Still great protection, but the gloves are not breathable in the slightest, and are only sort of waterproof. I still use them on days where there's no precipitation, but I still sweat into them and they end up soaked by the end of the day regardless.
Level, on the other hand, makes fantastic gloves, I absolutely love the build quality on the halfpipes, and they have every feature you could possibly want on a glove. The downside of course is that the protection just isn't as good as the flexmeters. They're still superior to most of the shorter standalone wristguards, but they work by a different mechanic so they don't actually feel quite as protective. The wristguard itself is very inobtrusive, I barely even notice it's there, especially compared to flexmeters, but even compared to other small wristguards they're very, very small.