I bought the CHOCOLATE Mainstays Contempo Futon Sofa bed from Walmart: http://www.walmart.com/catalog/product.do?product_id=10854953 earlier this year. It fits perfectly under a lofted bed. It has 4/5 stars from 715 reviews. I'd give it a 5/5. See link for details, dimensions and configurations.

Paid the full price plus tax at $173 (still have the receipt from 9/27/11 if you want to see). It's not even 9 months old. It's clean, no stains, and foam is still firm as ever. Must get rid of it by graduation 6/17/12. Will sell for $100 or best offer.

You will need to come pick it up yourself, but I'll help bring it out of the house. I live on the row btw.

*Simba and Domo are not included, sorry.