Since I don't own a .22LR rifle, how much fun are the S&W MP15-22's? Are the 18 inch Custom Shop versions worth the extra 200 bucks, and can they be fitted with a MAGPUL PRS like the Sport Models?
Can't comment on the stock fit or 18" version, but I love mine, it has functioned with everything I've fed it, including old nasty ammo that was given to me.
S&W has made a very reliable 22. If I didn't have stock in cmmg mags I would probably switch, but cmmg has also come out with updated mags with better feeding. The SW is not modular. You can buy conversion bolt and mag can go on any 556 upper and use your ar15 lower. There are also dedicated 22 uppers that pin right on an ar15 lower.
Depends on your goals.
I have had my M&P 15-22 for over 10 years. Zero problems. It is not picky about ammo and shoots cheap bulk ammo that would choke in my Ruger 10-22. The fun factor is very high IMO!
*edit: one thing that is superior on the 15-22 over the other .22 AR's is the mags! They are very easy to load, relatively inexpensive, which I think is a key to reliability on these rifles.
I have the 1st gen rifle and recently picked up a 1st gen pistol (no tube, 6” barrel) they are a ton of fun. Always one of the first few firearms I give to newer shooters, and they always walk away grinning ear to ear. The rifle has 12k+ rounds through it, half of which were suppressed. The only thing I did was change out the extractor. Other than that it’s been remarkably reliable.