Hi Squirrel,
You can see some comments about the Dream Star Natural Escape mattress and the quality of the materials in this topic and in post #7 and onwards in this topic and in posts #13 and #14 here. I would also make sure you find out the specifics of the materials inside it (see this article) because there are some discrepancies in the different descriptions.
This would depend on which one was a better match for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences). The best way to assess this would be with your own careful and objective testing using the testing guidelines in the tutorial post. For some people the firm would be a better choice and for others the plush would be the better choice.
Phoenix