My Observations: Shooting the M&P 45 and Glock 21SF
Picked up an M&P two weeks ago from my local shop to replace the 21SF that I didn't really like. I've long wanted a double-stack 45 and have tried quite a few including an HK Tactical. All were just too big. The slim-frame Glock and the M&P offered the most two attractive solutions to this problem. I had tried the Glock and sold it very quickly, it wasn't the solution I was looking for and so I looked to the M&P. These are my impressions of shooting both guns.
It should be noted that both guns were bone-stock and had nothing done to them. Moreover I AM a Glock fan, in 9mm it's very hard to beat.
Ergonomics: M&P is superior, using a small or even medium insert, my hand grasps it perfectly. The thinner frame eliminates much of the problem with undergripping that I had with the 21SF. Likewise it feels very much like a 1911 in terms of grip memory. Every time I would pull and point the Glock I'd have to adjust my grip as I found I had to pull the muzzle back to the proper index. If you have smaller hands like I do, than the M&P is really the best double-stack .45 option.
Controls: Glock slightly wins, The ambi-slide release makes this a nice choice for lefty's who have trouble dropping the slide on a Glock. I've adjusted so it's less a problem for me. The manual safety is similar to a 1911, so if you're used to that it won't be a problem. I do however prefer the simplicity of a Glock. My M&P also has a mag safety, which I don't like. I won't take it out.
Trigger: Again the M&P wins, bone stock it's just a better trigger than the Glock. Reset gives nice feedback and is a bit shorter than a Glock. Double-taps were surprising after the Glock. I'm not a fan of stock Glock triggers and the 21SF is no exception.
Sights: Glock wins: As bad as stock Glock sights are, I prefer them to the 3-dot setup of a M&P. My M&P came with night-sights but I really didn't like them either.
Controllability: M&P shot much tighter double-taps both in accuracy and splits (I didn't have a timer, but the M&P was noticeably faster). Recoil was a bit sharper with the narrower frame, but the Glock would slip/shift in the hand significantly more during rapid fire. The M&P stayed exactly where it should.
Accuracy: Slight advantage to M&P. Slow fire from rest, any differences were negligible. I'd have to try the M&P with better sights to be sure. Given better short-range, rapid fire accuracy, I'd lean towards the M&P as more accurate, but I need more information. Overall I shot the M&P significantly better, but this may be less of a function of inherent accuracy vs. grip, trigger etc.
Disassembly/Maintenance: Glock wins, the whole sticking the pin into your frame to disengage the sear seems a bit weird. The number of available Glock parts also gives it a nice edge. I know the Glock backwards/forwards and can totally disassemble it if I need to replace a part. I don't see why the M&P shouldn't be as easy to take apart.
Reliability: Glock probably but I didn't put either through a torture test (about 800 rounds over three days), but I'm pretty confident in shooting A LOT of rounds through a Glock with no more cleaning than a rag and some lube. That's not to say the M&P can't, it's just a question of confidence.
Conclusion: M&P probably wins, while the Glock remains my favorite 9mm it also has to be modified. The stock 21SF is simply too big for everyone, but if you have big mitts you should at least consider it. For the Glock you have to spend a little money to customize some of the features that an M&P has stock. The M&P also makes up for a lot of short-comings in other double-stack .45s (including the 21sf) and represents a unique and well-thought out design. While I'd prefer to have a few more rounds in the magazine (especially shooting matches) the M&P is a very significant design. More to the point I'm keeping the M&P and I ditched the 21SF. This being said I prefer the Glock in 9mm to an M&P in .45, but the latter has convinced me to try a 9mm.
