Markuson
SILVER Star
Do you use anything underneath the mattress on top of the drawers like plywood or something to make it perfectly flat? Sleeping in the back when I'm camping solo is one of the top reasons I went with these drawers but it's too cold here right now to try them out for that!
No need for plywood or anything else. Just get a decent self-inflating mattress that's 3 of 4 inches thick and it's perfect. The gap between drawers and folded-down 2nd row is a not issue with inflatables.
The mattress in my photo is an Exped-10. Not cheap...but fantastic.