Thirty rounders are fairly common in stores I've been to recently. Twenty rounders are what I've had trouble finding. There are several advantages I've found to twenty rounders such as bench shooting, confined spaces like a vehicle, and less ammo waste during practice. Don't get me wrong, I like my 30s a lot too. I already have a suitable amount of both, but you can never have enough. I paid regular prices (I'm a long way from paying stupid prices for them) for 4 20s and 2 30s. I can't buy billt numbers of stuff.