After fruitless searching at local furniture stores for an xl twin mattress, I saw this on line and decided to try it for two guest beds which my very tall (6'5") nephews use when they visit. The price was reasonable for a "real" (as opposed to just a slab of  foam) spring coil mattress. The mattress is quite firm, which I prefer. Definitely follow instructions for unwrapping and let the mattresses expand to their full size for 48 hours before putting bed linens on them. Mine didn't come to the full 80" length I hoped for, but very close after waiting for them to expand. The xl twin size sheets I bought fit a bit loosely.

Pros: Fast delivery, good quality, comes in the xl twin size which I needed for my guest beds
Cons: The mattresses were bursting out of their boxes on the day of delivery, which made them a challenge to move into the house by myself. I wish they had been more securely wrapped for delivery. They are rolled up like Pillsbury dough in a tube.