debating two mattresses

[njmattress]

Sam's club has a queen serta mattress and box top for $388. This seems like a fantastic deal... so good that I am considering taking back the mattress and box spring I just bought from costco.

This is the Sam's club one:

http://www.samsclub.com/sams/shop...promoemail

versus the costco one I bought:

http://www.costco.com/Browse/Prod...opnav=&s=1

The difference in price is $250 after tax... I know nothing about mattresses, but the costco one has 782 springs while sam's club has 504 springs. Is it worth taking it back for $250? Thanks for the feedback.

And for what it's worth the people using the mattress have a combined weight of 260 pounds.

Like I said, I already bought the Costco one and am satisfied with it, but for $250 I'd considering the other...