Anyone know anything about Englander hotel matresses? I'm looking for a hard doublesided innerspring mattress, with the intention of softening it with some latex or maybe memory foam on top. They seem to have several models in their hotel line that are double sided but no one around here seems to carry them so I can't get a look at them. I want something hard enough that it won't break down. I know Englander gets a lot of complaints about cheap foam breaking down but I am hoping the hotel models may be a bit more durable. Also, I notice one of the Englander hotel mattresses uses latex foam, which might make it more durable (though the question is "how much? remains}.