Origins Pocket, Origins Pocket Latex or Artisan?

Hi,
My Wife and I are after a king size mattress and are torn between the Origins Pocket (£570), the Origins Pocket Latex (£825) and the Artisan 1500 (£890).
My Wife is 5'5" and about 81kg
I am 5'9" and about 83kg
And we both like a cool bed.
Can you please advise us on which would suit us more, the Artisan 1500 really would be the absolute maximum of our budget but obviously we'd be happier with the cheaper models as long as they suited our needs.
Thanks,
Pete