We went for one week, but went with relatives that stayed for two weeks. We went for the first week in the season, which I wouldn't recommend (they were still training the staff), but it got a lot better towards the end of the week, and was fantastic the second week - after we'd gone!
How old are your children? The kids clubs seemed good, but ds was too young.
Would def. go all inclusive, otherwise the food/drink would get v.expensive. You got drinks in your room fridge with AI, which I haven't had anywhere else.
Rooms were great - separate bedroom (two doubles), lounge (sofa bed and we had travel cot in there too), fantastic bathroom with sep. bath and shower and fully fitted kitchen with microwave and cooker. DS is gluten/dairy intolerant, so I could prepare all of his meals in the kitchen, which would normally be diff. if you're AI.
Bars and entertainment great. Pools fab, esp the pool complex across the road (linked by a bridge). Easy access to the two nearby towns (Benalmadena, and forget name of other one) by bus which stopped outside hotel. Train station in near town so you could get the train to other areas if you did two weeks. Car hire seemed OK prices.
Our relatives did the Majorca one last week, and said they preferred the Costa del Sol one.
I found it a v.cheap holiday - once you'd paid for the holiday, there was almost no extra spending - certainly nothing in the resort.
Ask away if you've any specific questions :)