I had a Glock M23 years ago and sold it as it tended to induce a lot of flinch after only a few mags shot. There seemed to be a lot of barrel "whip" so I sold it. I picked up a Glock M27 .40 and it has been one of my primary carry AND competition guns ever since. The M27 also accepts both the M22 and M23 mags and I have several of each of these hi-caps. You can even get a "spacer" for the M23 mag so it fits the M27 seamlessly. I have not had any "whip" with the M27.