We booked this as a last minute, and never having been to Majorca, really had no idea what to expect.
Cala Domingos is a really beautiful complex - lots of flowers and trees, pretty apartments disguised as little white houses, two good pools - we were delighted!
The apartment was fairly roomy and very clean, with a lovely balcony.
We ate once in the Cala Domingos restaurant, but it wasn't very good - most nights we just walked across the little beach into the resort, although I have to agree with the previous reviewer about a lack of good restaurants... Calas de Mallorca is kind of more like a big shopping centre than a town, but the kids loved the mini-golf and other kiddy type entertainments, and we were all happy enough :)
There was entertainment every evening in the Cala Domingos bar, some kids stuff, talent contest etc, but I think they were pretty much winding down by the end of September. It was quietish, but very relaxed. There didn't seem to be any daytime activities around the pool, and although there was a kids' club, it was quite often cancelled, due to there not being an awful lot of kids going to it. That did disappoint my son a little - he's the sociable type and had been looking forward to the kids' club :)
All in all, though, we all really enjoyed Cala Domingos - it's very pretty, and I imagine it's a lot more lively during peak season.
Hire a car and see the island - it's gorgeous when you get out of the huge resorts :)
