I chose to buy a futon over a sofa bed. But I chose a better quality futon. Not the black pipe line thing.

I've spent time on sofa beds & even with the new inner spring mattresses, they are really uncomfy. I think I actually prefer the old foam mattress.

My futon isn't so bad. You need to be careful you don't tip anyone off in the middle of the night, but I've spent a lot of movie days on mine & don't mind it