Another thing to consider too, and I found this out when I was buying a mattress. You need to bargain with the sales people on the price. I read that you should ask for 50% of what they are listed as (even if they are already having a 50% off sale). When I did that I ended up getting around 40% extra off the mattress I bought and the included free delivery and set up (Which was probly included anyway).
A lot of you probably know that already, but since this was my first time buying a mattress I never would have thought about that.
Also, I guess they don’t do bargaining at name brand stores like Tempurpedic.