the jack knife sofa should have been outlawed years ago. horrible sleeping sofa. we had one in our first TT . i slept on it in living area and wife slept in bedroom due to my snoring and being cramped in a small rv bed. i almost rolled off the thing several times.
after about 3 months i ripped the jack knife sofa out and sold it on craigslist for 200.00 to a fellow customizing a large cargo trailer into a toy hauler.
we bought a thomas payne tri fold rv sofa. it was actually not a bad sleeping sofa bed. the foam material for me was comfortable.
they aren't cheap a little over 1200.00 but for me a good nights sleep is priceless.
our current TT came with one already in it and i continue to sleep on it. i do put a 3 inch foam mattress pad on top for extra comfort.
im sure there are others out there people will chime in on that are good as well.