Futon frame construction-which is better?

Posted under sofa futon

I am looking to buy a full size futon sofa bed. Bifold is good and so as maple, ash and oak but what about construction.

Is tounge and groove or mortise and tenon construction better?

Also, do you know of any good website store that sells good quality futon sofa bed for a great price?

tounge and groove or mortise and tenon construction are both good. They are all glued together and the wood will break before the glue joint will ever break.

This place looks pretty good if you want a lower price.
http://www.everythingfurniture.com/futfutsof.html
this one is interesting
http://www.bigfuton.com/
These are nice
http://www.totalbedroom.com/futons-bed/
http://www.norkafuton.com/
http://www.futonfurniture.com/