Hi pinupchick,
I did a little bit more research in the London area and talked with a couple of the SleepFactory outlets as well (I hadn’t talked with them for a while). Their house brand used to be made by Springwall but they have now changed manufacturers to Endless Comfort. They are a group of franchise outlets and some of them are more knowledgeable and accommodating than others. Some of them also carry different models than others (each franchisee can choose what they want to carry on their floor). Any of them should be able to phone the factory to find out the layering and density of the foams in their mattresses though (besides just the 3" comfort layer which is very good quality polyfoam). This way you would have a better idea of any potential “weak links” in your mattress.
ADMIN NOTE:Removed 404 page link | Archived Footprint: endlesscomfort.com/
I also updated the Southwest Ontario / London, ON list so that others in the area will have more updated information.
Phoenix