Me, too, as well as on LH. Never been denied entry (though I would not have missed much). I haven't flown UA Y from DOH yet, but, since UA uses this lounge for premium passengers at least, I would be very surprised if they didn't let *G in too.

The lounge is not dry, however -- there are a alcoholic drinks available on request, and usually a little menu placard in the drinks area.

FoxFlyer, you won't be able to use the QR premium terminal but should be able to use the lounge that UA uses (Oryx).