If I get one, it will most likely be a bolt gun. My opinion has long been that on an AR15 format, the 223AI has about all the case capacity you can effectively use. I'm sure a 22 ARC can get slightly better performance, especially with the heavy stuff and a long tube, but the gains are small enough that (for me) it wouldn't be worth the cost of the more expensive brass. A bolt gun, on the other hand, could be a different story. Even if you're not getting every ounce of speed you possibly can, you should still be able to pick up at least an extra 200 fps over a .223/5.56 load without being hard on the brass. There are other cartridges out there that operate within the same range (22ppc, 22Hagar, 22BR, ect), but the 22 ARC currently has some factory support, and even if it didn't, once fired 6.5 G brass should still be reasonably priced, and easy to work with. The thing I'm looking to see is whether or not the 22ARC has any practical advantages over the bigger options like the 22-250 and 22 Creedmoor. I realize that in practice, the advertised claims that the 22 ARC rivals a 22-250 is a total load of BS (embarrassingly more so in an AR15), but for something like Prairie Dogs, burning noticeably less powder in the barrel could help keep the temps down so you can get a lot more rounds on target.