Russell,
I went to Atlantic Parks last month and had a great time! I took my boyfriend for his 30th. We stayed in the timber lodges that they have on the website. They are really cosy and romantic. We didn't manage to get to the beach but we did have long walks in the park. It was as nice as the picture on the site and more! I'm really bad at organizing holidays but i just rang Becky from the website and she sorted everything for us. She even organized us being picked up from the airport in Gibraltar and taken back. It's only just under an hour away from the airport so your not spending the whole 1st and last day of your trip traveling, which i hate!
I think that if you do choose to go to Atlantic Parks, you won't be disappointed.
Hope this helps!
Kendra