The A350 bunk is marginally better than sleeping on a floor due to the hard mattress. I find the new mattress no better. I started to bring an air mattress - extra wide to stay in place. It was small and easily portable. It meant much a better quality sleep. but started losing air after the 5th trip. A little research pointed to the loss of air being a consistent problem with all/most? air mattresses. So, I bought a self-inflating pad which works ok, but is much more of a pia to carry. Alternately, I have seen a FO carry a foam mattress that provided reported luxurious sleep, but it was a monster to schlep around. I'm 6'3' the A350 bunk is a perfect in length and width, but less than generous in height. Many wear earplugs as the FAs can be loud on 1st and 4th break. The 777 was vastly superior, but so was the entire aircraft. The A350 is what we have, pays well, and the crew rest is nothing more than adequate which rate a little higher than most of the stuff DAL provides its workforce.