Iam trying to buy a bed that would give me a real 8Hr sleep (No Back Issues.. etc, But need to throw away my existing mattress)

I initially wanted to buy Tempurpedic - But this costco price is attracting..

http://www.costco.com/Browse/Productgroup.aspx?Prodid=11473343&whse=BC&Ne=4000000&eCat=BC|93|1924|78455|67414&N=4034765&Mo=7&pos=1&No=2&Nr=P_CatalogName:BC&cat=67414&Ns=P_Price|1||P_SignDesc1&lang=en-US&Sp=C&ec=BC-EC25093-Cat78455&topnav=

Any feedback on this mattress.

Also how true is the entire talk about memory foam beds being Hot?

If someone know more - how does these costco/sleep science beds stack up against the tempurpedic mattresses?

Alternatively - Also looking at some natural latex beds - http://www.sovn.com/ -- But these are getting expensive as i move along to what i want.