Really nice, and the price is right! I’ve had this bed now for more than one year, and it has held up great. We use it in a rentalguest cottage, and it gets quite a bit of use. We have an extra long XL twin Memory foam￼ mattress on the top, and a regular twin memory foam mattress on the trundle. The top mattress is 10 inches thick, and the bottom mattress is 8 inches thick. 8 inches for the trundle mattress is just about right. If you really want to be able to slide the trundle out easily, I would suggest that as your maximum depth. I had a cover made for the top by someone on Etsy so that when It’s made up as a couch, it has a little bit of an upholstered feel.￼ I plan on ordering this bed again for another room. I will likely choose the exact same mattress configuration. A regular twin mattress on top would work fine, too. I just wanted it to be kind of a snug fit without gaps.