So I think I am going to give up on my SleepEZ mattress. No matter how I configure it and top it, it still feels too soft in some positions and too hard in others. Guess I'm just not an "all-foam" bed guy. So, what I am thinking is, since I have some nice latex layers, I'm gonna buy a firm, durable inner spring mattress and top it with a layer of latex. To increase mattress life I want one that I can flip from time to time. So the question is, can anyone recommend a brand? Firm, good springs, flippable; essentially a foundation layer for the latex. Thanks.

Steve