They work great as long as you get the smallest possible size so they fit nice and snug. They are also used by session players to extend their ability to play for longer sessions. So def not just for newbies!

I don't use mine anymore, but I sure did when I was re-developing my calluses. Never had to stop playing because it hurt -- and that makes for faster progress. I'll take them over the whole "paying your dues" pain thing anyday. ;-)

Moe, I get what you're saying. I've actually spent about 20 years studying things like pain initiation rituals and rite of passage and there is absolutely value and power there. In this case, though, IMO learning to play guitar is already challenging enough that there's no need to add pain for pain's sake!