Back about 1982 or so I started accumulating .22 conversion units or .22 cal equivalents of my various guns to allow me to practice for cheap. My normal practice has been to shoot about 1000 rounds a month of .22 indoors in the winter.
In January I bought the first Glock 44 I ever saw. I already have a Ciener conversion unit on a G19 frame and an Advantage Arms conversion on a G22 frame.
I've been REALLY impressed with the Glock 44 so far. I have tested it with the following ammunition types:
200 rnds CCI Mini Mags. (40 grn at 1235 fps)
300 rnds CCI AR Tactical. (40 grn at 1200 fps)
200 rnds Winchester M-22 (40 grn at 1255 fps)
200 rnds Winchester Super Speed (40 grn @ 1300 fps)
200 rnds Federal Black (38 grn at 1260 fps)
200 rnds Browning Performance Rimfire (BPR) (40 grn at 1435 fps)
200 rns Armscore High Velocity (36 grn at 1260 fps)
200 rns Augila Super Extra High Velocity ((40 grn at 1255 fps)
That's 1,700 rounds in five weeks.
I cleaned and lubed the gun after each trip to the range.
I had NO (0) malfunctions.
Most of the shooting I did was accuracy drills on NRA B-24 or B-34 or B-29 or TQ-20 targets at 30 and 50 feet. I also shot on some Warren Tactical WTS-8 targets at different distances.
Both of my other Glock conversions and the SIG factory .22 conversions require hot ammo with plated bullets to run reliably. I've usually used CCI Mini-Mags for that application, and still experienced occasional malfunctions caused by the slide not going fully into battery.
So far I've been really impressed with the G44. The trigger feels like a stock Glock trigger.