Hi Cotton,
Royal Bedding’s two sided mattress and topper combinations are a good design that also have very good flexibility IMO (you can replace the topper without having to replace the entire mattress if you need to down the road) and I think highly of the design (see post #4 here). The base mattress has the durability benefits of a two sided mattress and the topper provides some of the options and flexibility of a component mattress (see post #3 here). They use a very high quality pocket coil and the latex they use is a blended continuous pour made by Latexco which is also a high quality material. Interestingly enough Tom was never a fan of pocket coils in general but the quality and weight of the steel in the Texas Pocket Springs was what changed his mind about using them in his mattresses.
While nobody else can tell you what is “best” for you … there is more about the most important parts of the “value” of a mattress purchase in post #13 here and if the mattress/topper is a good match for you in terms of PPP (Posture and alignment, Pressure relief, and Personal preferences) then it certainly uses high quality materials and is a very durable and flexible design and is certainly “good value” compared to other similar mattresses as well. If I was in your shoes I would certainly give it very serious consideration as a final choice (see post #2 here about making “final choices” between “good and good”).
Phoenix