I've been looking at this one, a good price and good reviews... but I'm still on the fence, it's about the nicest one for the money that I can find currently and it has a lot of very good reviews so far:

Sleeper Sofa

Hmm no pic of it open though.

Yeah, that's on the full, here's the queen, there are pics with it open:

https://www.wayfair.com/Benchcraft-Zeb-Queen-Sleeper-Sofa-BNCT1234.html

Consider a futon. You can get one with a really great mattress and bolster pillows etc to make it look just like a couch when you aren't sleeping on it. Much more comfy than any sleep sofa I've ever tried.

Nope, did futons a while back, not comfy in my book, more like a slab of lead. A sleeper with a piece of plywood under the mattress and a foam topper is sublime, perfect even. And, IMO, futons always look like futons when they're not in bed mode. I want this to look like sofa.

We previously had a futon like couch and it wasnt comfortable. No more. We had to put a blow up mattress on it and even that wasnt comfortable for some of our guests with bad backs.

When I bought mine I spent a lot of time researching and bought it from a source that offered 12 different mattresses, each of which I tried before buying. The mattress on my futon is outstanding, so sez all of the houseguests that have slept on it (and that includes my sisters who wouldn't hesitate to criticize if necessary). But to each his/her own...