Trying different combo's for a pair of kingsized beds.  Need 2 beds anyway so I have 2 chances to get it right (the other will be a frequently used spare bedroom).

 I have FBM latex 6" core and 4 seperate 1" toppers of diff softness to change around. 

Some here have said they prefer the latex over a coil springs.  Since I can't take that back, or exchange it like the latex, does anyone have a suggestion for a good, well made, firm coil springs to serve as the base. 

Cost effective is important, but not the top priority.  So far Original Mattress Factory has their best for just under $700 with tax and delivery, but I don't know If I need that good since it will have 4" of latex over it.

I assume those that want the coils over the latex base do so for the added firmness of the coils anyway, but what do I know?

Jeff,

I think what some folks are saying is that they like just a regular innerspring mattress with a latex topper of 2"-3".  You could put a 6" latex core over box springs but it wouldn't be recommended. You really want a nice smooth foundation for it to go on. I personally wouldn't put latex on box springs, but these newer smooth box foundation pieces(no springs) work fine and they are very inexpensive. I see the wooden slats being recommended and I understand the breathing concept, but I would not use them myself as you can actually feel any irregularities in the foundation. I know that sounds strange, but you can feel any irregularities under 8" of latex.

I understand but may have worded it poorly.  Coil springs refers to the mattress itself, not the base (or box springs).  And yes, I would put the thin latex layers (not the base latex) on that. 

I just wondered if anyone had any recommendations for a good, firm, yet cost effective "regular mattress" (not box springs) to use under the thin latex topper layers instead of using the 6" latex under them.

There was a very long thread about those who didn't like the all latex feel, and suggested they found this combo to be their favorite, I was hoping some of them would comment.  I'm just trying to learn from others trials, but still know its opinion.

You know, I would research what coils are in what beds, and try to find one lightly used...cheap...after its pillowtop has gone flat.  The coils aren't the problem usually, it is the foam on top!!! 
Kait