I got it from Amazon and the measurements were 1" off in both directions. Not really much at all and damned if I don't sleep like a wee little baby on it. Not only that but it doesn't stink. Smells like mint chocolate. These are two pluses for a big and portly guy.
It had really good reviews and a lot of them. Works out very well for the two sofas made into a bed. I highly recommend. Two thumbs up.
And in case you are wondering, yes I've slept on it numerous times to verify it's comely goodness. Normally I can't sleep in because my back hurts. Best I ever make it 8:00 in the morning. I slept till past 10:00 on this. Me likes.