I’ve used the ones slim showed in his pictures, better than the old compression type, but you want to make sure your pex is lined up pretty well with the fitting. The collars have a couple of “hooks” on in that fit into a groove on the barb part of the fitting, get a little off and you can’t get both “hooks” into the groove on the barb, can be really aggravating, especially if your fighting them well below freezing and its snowing. And don’t let your “help” tighten the bolt on the collar or you’ll be digging thru your install trailer, the bed toolbox and the ashtray in your truck trying to find another metric bolt.
The barb is heavy duty though, nice thick walls, the OCD part of me wanted to run a drill bit thru it though and enlarge the hole a little.