Hi ineedreem,
My reply was delayed with your ongoing conversation which pushed the thread further down the list. Sorry to reply to your post “out of order”.
I actually called them a couple of weeks ago because of their site being down and you can see the results of my conversation and my thoughts about them in post #9 here. I certainly wouldn’t worry about the state of their website which isn’t one of their main focuses and some very good manufacturers don’t even have one.
The design looks one sided in the diagram but if it’s just an illustration and it’s actually two sided then that’s certainly a bonus. I actually like this type of design a lot (mattress and topper that are tested together and work well together with no weak links). The “base mattress” has the advantage of being flippable for greater durability and the topper can also be flipped and also replaced without having to replace the whole mattress if it wears out faster than the support layers (which is usually the case in all mattresses even with a topper as durable as latex). It can also be replaced if your needs change down the road again without buying a new mattress. Toppers under a protector or sheets don’t have a shifting problem … especially with latex which is heavy.
All the materials in the mattress are good quality and I don’t see any weak links in the mattress. Assuming that it’s in your budget range, and the combination tests well for PPP … it certainly seems like a very good quality combination.
No kibosh from me 
Phoenix