Sears offers the Serta Coralee II Queen Mattress, model no. 500555681-1050, for $149.99. Coupon code "SEARS5OFF50" cuts it to $144.99. With $69.99 for shipping, that's $230 off list and the lowest total price we could find. It features Serta ComfortRight layers, Serta Pillowsoft foam, and a 420 SertaFlex Innerspring.
Of note, Shop Your Way Rewards members will earn a Sears credit with this purchase and may be eligible for additional credits and discounts.