hi cfc fan, have always wanted to stay in the Maspalomas Tabaiba Princess but it is bit expensive for us. There is a pool like a man made beach if you know what i mean, the situation is good, with a 20-25 min walk to the famous maspalomas sand dunes/beach, with its fab bolouvard of shops restuarants bars etc. Also you are about a 10 min walk from the Faro 2 cc, PDI is a 3-4 euro taxi rde away, and in the other direction Maspalomas beach. The area is very safe and so is PDI but it is up to the individual to be aware.

Id probably err towards masp/tabiba too, defo the nicer of the three (though there is post on here somewhere that says otherwise). nicer location too.
GCP is nice and central and is still a really nice hotel, nothing to grumble about either
Riu flamingo, a little older i believe and maybe a bit dated. I think its and aparthotel, so you would have self catering facilities, but still be on HB. With it being a Riu, the entertainment should be good.

A hard (but nice) choice, i think it would be Maspalomas, the resort is lovely, the sand dunes are great its close to the "action" of playa del ingles but far enough away for it to be peaceful.

Regards you daughters, and drinks etc....its the same as it is in the UK. be sensible. dont take drinks from strangers, dont leave them unattended and dont get stupid drunk! Alot of the "spiking" in holiday resorts (and it is still rare) often turns out to be too much booze...drinking by the pool all day, wine and beer with dinner and then going crazy at night after all that sun.

And thats my tuppence worth! Have fun choosing which is you fav hotel... i was going to say not to worry about your daughters, but i guess as a parent you cant!!