DH has slept on the ceiling bunk with no issues and he's 5 10. I will admit I was a little nervous sleeping under that, LOL, but I just kept reminding myself he is well under the weight limit.
I am 5'4" and I slept in the top bunk no problem. My child slept up there when they were 5'7" but when they grew a couple more inches, they were more comfortable on the sofa bed.
If you are 5'8" or less, maybe. If you are any bigger, no way! My teenage son had his feet and ankles hanging over the edge the last time we tried to fit all of us in one room.
I was fine with it for our last 3 day cruise but I'm 5'2", well under the weight limit, and in good physical condition for going up and down the ladder. It's a small space so I could see where more averaged sized adults might be uncomfortable.
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