Craig, if one of you will be sleeping on the dinette regularly, I would suggest a
Coleman air mattress, plus a 12v pump. I have a double-mattress setup for my king bed, and it takes me about 2 minutes to inflate both. Should take 30 -45 seconds to inflate a single, or a minute to inflate a queen size, if you go this route. A
12v pump can be cheap (I have the
Coughlan's pump, and am very happy with it), and the air bed will be much more comfortable than the dinette cushions.
Actually, I would recommend it for the Queen end, also, as we have the air mattress, 3" foam, and a good double-wide sleeping bag. I leave all in-place for travel, which we could not with the original foam mattress. Just as comfortable as home bed.
Enjoy doing all your mods to your new TM!