I've recently used black PlastiDip on the bottoms of my converted (for a 9mm AR) UZI mags. It makes them a bit nicer on my palm when I slap them into place. It took several coats (4-5). The next day, I peeled one off just to be sure that it was easily reversible and that it didn't run up the mag-well. It didn't appear to pass the floor plate. I plan on doing the rest this way too.
I'm thinking about Doing this to my Tango-down stubby VFG too. I like the texture of the stuff and use it on pliers and tools. I've thought about adding sand to it for a more abrasive texture though.
I tried the spray on, and to me, it's not as good as the dip. Besides, the spray gets very messy.
Once you crack the lid on a can, plan to use it all within a month or two. The snap on lid doesn't form the best seal.
I did this today to a plain Jane black MOE grip. Dipped once and allowed to dry 30 minutes. Sprinkled fine dry sand from a plastic cup with small holes in the bottom like a salt shaker. Dipped a second time and allowed to cure. Rotated the grip to prevent drips and runs.
Damn thing looks and feels fantastic.
Magpul is truly missing the boat on the overmolded MOE+ as it would no doubt prevent lost sales to Ergo, Tangodown or others that have rubber like grips.
In the mean time I'm going to do several other grips and vertical foregrips as well since it came out so well.
Wish the PlastiDip was available in FDE though