I always kind of considered them a joke/novelty, until I got my first in a trade a couple of years back. Now I have three, all 22mag versions.
Been carrying one in my back pocket behind my wallet for a while now in a Desantis pocket holster. Works pretty good too. Still a novelty, and more to screw with my buddies than anything serious, but, it'll work in a pinch.
Once you figure out how to aim with them, they are actually pretty accurate. My PUG has "Big Dots" on them, and is aimed like you'd expect. The other two just have a blade type front sight, and you dont want to try and aim it like you normally would. Just use the blade for windage and sight along the top strap of the the gun. If you do that, youll get good hits, and farther out than you might think.
This was shot at around 5 yards in just that manner.
This one was shot at around the same distance, but as fast as I could thumb them off...
Mine came with a number of different grips, some on the guns, some off, mostly small, wood and plastic, and one came with the pocket folder. The pocket folder works, but its big and bulky.
The one I came to like the best, pretty much instantly too, was the Houge rubber grip that came with the PUG. I put one on each of the others too. Its small enough to be small, but its fat enough in the right places to give a very good and comfortable grip and makes shooting the guns very easy.
The only time Ive had any issues with ammo, was with this box of Remingtons that came with one of the guns. Figured I shoot it up in practice and found this...
Even keyholing, they still shot fairly well.
Havent run across that with any of the others either. The Remington also miked small when I measured them, barely making 0.220, and some miked that on the case, and not the bullet. All the others were right around 0.223.
And of course, for the older crowd that grew up with Matty Mattel. Gotta have one of these to annoy the antigun inlaws at Christmas.