There is technique involved with using (as well as cleaning and maintaining) these guns. Otherwise they will not work as expected.
One thing that took me a long time to learn (by making a lot of mistakes, and realizing I was the problem) is that if you are having problems soldering or desoldering, *regardless of the tools you're using*, the issue is almost always a matter of technique. As long as you have functional tools and quality solder (which is key, do not use cheap Chinese crap), everything else is technique.
When pads get ripped, the cause is either not getting enough heat far enough into the joint, and/or putting too much pressure on the pad. This is why when using guns you want to desolder with the board held *vertically*. The tip of the gun shouldn't press on the pad at all. You hover it above the joint, only making contact with the fresh solder ball (which you added first), and the pin itself.
When people lay boards flat on the bench and start grinding the gun into the board, that's when you get damage.
Another area where people have problems (which I see regularly on boards) is not getting heat far enough INTO a joint. If a joint has a power or ground plane on the parts side (or even just a thick trace), that metal will suck heat away from the joint on the parts side, even if the solder side is liquified. This results in not getting a clean pull, because the solder is melted all the way through the hole. You can tell when this happens because if you look into the hole you'll see a silver 'cup' of solder remaining, instead of a clean hole.
So people crank up the temperature on the gun, thinking that will fix the problem. But it doesn't. It just adds more heat to the SOLDER SIDE, which melts the adhesive and results in ripped pads and traces, even though the parts side can still be solid. The key is to get more heat into the parts side.
It's small stuff like this, but it makes all the difference between making things easy, and tearing up a board. But ultimately if you are causing damage, it's YOU that's the problem, not the tool.