Unconfirmed here, info from people playing DMM (since hek, with cymbidium and dendrobium in Limited 1, why would you roll anything else? XD):
1x roll should give 1x lv20 dragon as a gift, whereas 11x should give 1 or 2 lv100 ones. And indeed, it's Premium gacha with freebies, so it should be good when not saving&uninterested in the new spotlight