Just returned from Paleros, thanks especially to Paula1 for all the really helpful advice.
It really was a FANTASTIC holiday, each of us really enjoyed ourselves. The Nannies exceeded all expectations, great clubs, great activities, our 6 yr old loved his club and was one of those children who wanted to be there rather than with us (and this is a shy, quiet child we didnt think would go in the door of a club). He did a different activity each hour; sailing, windsurfing, waterskiing, tennis, football, rounders etc.
Toddler shared a nanny with 2 other children, they had painting, out on bug hunts, jumping waves, sandcastle building, ice cream trip, bikes and trikes, again changing every hour, so you could plan your day and when you were picking up and dropping off. I usually used to peep through various trees, bushes and cracks of door to see if he was happy or sobbing!! They were open 9-1 (then you had lunch together) and open again 3-5pm.
The food was so much better than I thought it would be, and the 5pm kids supper was good quality, no nuggets there! Grilled chicken, pastas, etc. Lots of milky mousse puds, jelly and a huge bowl of fruit salad every night.
Toddler pool was really shallow and perfect, spent hours in there.
Baby listening service worked well, they really do check your door every 15 mins, and come and get you from dinner/bar.
Good flight and transfer (3hrs and then 30 mins coach). Both easily managed.
(Found a good hotel deal at Gatwick for the night before in a family room through abc holiday extras I think its called, on the web.)
So, yep, we thought it was brilliant and would really like to save up and go again next year.