Memory foam questions

[Greenhand]

We need to replace the interior cushions in our saloon only. Since this will be our main living room, as well as sea berth, I am considering memory foam.

For those who know, or have used memory foam, would it be better to use all gel memory foam (4"-5") or to layer a denser foam on the bottom with a memory foam topper?

Also, with memory foam, do you still use batting?

[boatpoker]

Rather than batting, I suggest 1/2" plywood. Touching that memory foam stuff gives me the willies.

[model 10]

If you butt is getting pointed, a cushion with 3 layers of different density polyester foam is pretty nice. The cushions I've made have always had some batting. I found the fabric will stick or chafe any foam unless you use at least a very thin batting. Not all pro's do though.
The cost of that kind of foam is crazy.