Well, I haven't actually used them at an event, first time I brought them was the Oct. 11,12,13; and I NPC'd first night (and hadn't gotten them checked by that point), there wasn't real combat situations besides melee tourney the next day.
I've practiced a bit with my brother. I have experience archery prior to this, though I'm by no means an expert, and with a 24lb larp bow, they can be fairly accurate at about 20.' I can get in the right area at 30' if I arc the shot; after that the drop off seems to be too much for anything other then luck, and I don't think a bow with more pull would be what I want, safety wise. Not until I get a better feel for it, at least. They could have some good situational uses, depending on the makeup of targets in the area. For example, that first night on the 11th a few arrows into the crowd of NPCs would have been some great targets to hit; a great cluster of bodies, no shields.
As far as getting hit by them, the dozen or so times I had my brother shoot me (I didn't want to use them until I knew what they felt like), they felt lighter then an average melee blow. Mostly at about 10' to 15.' The only other major problem is conveyance of the arrows. I don't own a quiver for the larp arrows, and they'd probably get hung up on it anyway when trying to pull them out (they're not really designed to be shot from anyways), and I can't stick them in the ground to pull and shoot later. I've a couple solutions in the works, but wont know how well they are until I try them out at an event.
If people wanted to try it out, I'd be more than happy to let them use my bow/arrows whenever I bring them, and offer a couple basic pointers.