When my department switched to the Glock 31 last year, I traded my 19 in on a 32C. Me and my partner went to the LGS, and they had only 2 32's left. I let me partner get the 32, and I got the 32C. I was wary of this (as was my partner) because of all of the bad things I had heard about compensated pistols as defensive firearms (mostly rumors and in print).
Since everyone locally had snatched up everything Glock in .357 for 60 miles around, I went ahead and bought it - there wouldn't be any 32's around for awhile (my ADD keeps me from being patient).
Well, I will run down all of the negatives that I had heard about compensated pistols, then I will line out my experiences with them.
1. A comped pistol fired in a close combat/weapon retention position will spew fire/hot gasses into the face and eyes of the shooter, causing pain, possible injury and an inability to carry on the fight.
2. A comped pistol will reduce the velocity of the round to a level that will make it less effective on target.
3. A comped pistol fired at night will create a flash-blindness greater than that of a regular pistol, decreasing effectiveness of the shooter in low light.
4. The comp really is not effective - it doesn't control muzzle rise that much - it's not worth it.
5. The comp version is less reliable than the uncomped version.
I had heard these things more than once, and probably passed them on to others as gospel, since they came from people I more or less trusted. Since I wanted a new pistol in our new caliber, I bought the C model anyway to see if they were worth it as a defensive pistol.
Here are my findings - they are my opinion only, so don't take them as gospel. I am no expert, but I do carry a gun every day as part of my job, and I take their use very seriously. All of the below results were with Speer ammo (either 125 FMJ or Gold dot 125 grainers). I wasn't willing to go spend money testing ammo my department doesn't use. Sorry. I'm a poor cop who has a mean wife.
1. The "fire in the face" issue. Dispelled this pretty quickly. I qualled with this pistol the day after I got it. The first stage of our qual is a one-handed close combat/weapon retention postion stage at 3 feet. The weapon is drawn and fired held close in (about armpit height) close to the body. On the range, I did notice a slightly higher pressure in my nose as I fired it, but nothing that you would notice in a gun fight (I get this on pretty good authority ). My eyes were completely uneffected, there was no burning anywhere. It was less pressure than being in a room with a FDD (flash-bang) by far. I have qualled and practiced with this pistol numerous times, and shooting close to the body is not debilitating at all. That said, I would't recommend putting your eyeball or mouth right over the comp ports. This might be uncomfortable.
2. While I have a chrongraph, I'm too lazy and/or forgetful to take it to the range very much. Luckily, I went to a terminal ballistics workshop at work, and got to shoot some jello (calibrated ballistic gelatin) over a chrono using dept ammo while getting paid OT and getting served free lunch (life is hard sometimes, but I make sacrifices). We were able to shoot lots of ammo from lots of guns. I shot both my 31 and 32C, and someone else shot a 32 (non-comped). To make a long story short, there was no difference in the performance of any of the guns ballistically. The 32's (both C and regular) shot slightly slower with the ammo we shot (Speer 125 gold dots). The difference was about 10 fps. I'm sure over a statistically significant average, there might be more difference, but this told me that I needn't worry. Also, the difference between the full length and shorter barrels was about 50 fps with that ammo in our guns. Penetration and expansion were almost identical - actually the shorter guns penetrated about 1-2" inches further with almost identical expansion. I can't figure that one out. After a day of shooting, I had great confidence in my pistol/ammo combo (at least in blocks of jello and through various barriers).
3. This one took me the longest to address. I generally weasle my way to the range with my boss's permission early (at the begionning of shift or right when I get up before work), so I do less shooting at night than I should (I'm out trying to catch bad guys at night). However, a few weeks ago, we had a dept-wide night fire training. We shot in BAD (butt-ass dark) conditions from inside cars, over and around our cars, and from various types of cover/concealment. I left my issue 31 at the PD, and took the 32C to see how it fared (since I work plain clothes, and carry it more often anyhoo). I expected huge fireballs from the comp ports, and general flash blindness. I was disapointed. The flash was there from the ports, but my recovery speed from the flash was no different than from that of any of my other pistols. I could see and shoot just fine, and the fireball from the ports was very subdued. This might be different with different ammo, but with our setup, the flash is not blinding (we shot both with and without white lights in case you are wondering). Again, I came away confident in my weapon an ammo in such situations.
4. I have shot the 31, 32, and 32C right next to one another. At least with the .357 sig ammo, the comp makes A NOTICABLE DIFFERENCE. The muzzle rise is almost non-existent, and follow-up shots for me and everyone I have let shoot this gun are much faster. It is much more noticeable shooting from barricade or akward positions. The comp really does work - at least with this gun/cartridge combo. If you want to know about another combo, ask someone else.
5. I have in a year +'s worth of shooting to experience a single malfunction. I know nobody who had a C who has had any problems with their pistol working.
Well, this is my experience with this pistol so far. Maybe it will change as I go along, but I doubt it (if nothing else, Glocks are boringly consistent - I think that's why 1911 owners hate them: nothing to tinker with). I consider the C models of the Glock to be absolutley suitable for personal defense / duty weapons based upon my personal experience. I have fired a lot of rounds from my own little Glock, and am absolutley satisfied with it's performance.
PS. I might get off my arse and actually take some pics of the 32C to post along with it, but I haven't gotten motivated enough yet.
Bought an extended ported drop in .357 barrel for my G22 nice virtually no flip or rise at all. Magnum power and 9mm handling. Usually practice in 40S&W eats cheaper and buyable in bulk.
I have a Glock 23C and heard the same stuff before purchasing it. I did not test it to the extent that you did but all of the "issues" with carrying a compensated Glock were no where to be seen. I carry it daily and love the way it shoots.