I've shot them, well before the current warnings about the guns coming apart. The bullets were hard cast and there was no lead build-up, which is the key to success I think. Polyagonal rifling will do just fine with lead bullets that are the correct size and hardness, same as any other rifling.
However, it is up to you. A cautious person would test a few at a time (remove the mag between shots to leave powder gasses a place to vent if necessary) and see how much build-up there was. A more cautious person would get an aftermarket barrel, and the most cautious of people would not shoot lead bullets of any kind in any Glock.
Keep in mind Glocks are occasionally reported as coming apart with factory loads. Sometimes things happen.....
However, it is up to you. A cautious person would test a few at a time (remove the mag between shots to leave powder gasses a place to vent if necessary) and see how much build-up there was. A more cautious person would get an aftermarket barrel, and the most cautious of people would not shoot lead bullets of any kind in any Glock.
Keep in mind Glocks are occasionally reported as coming apart with factory loads. Sometimes things happen.....