I have only been on one Holland America ship, Veendam, but the beds on the many Princess ships on which I have sailed are just as good, or better.
If your father-in-law has a special need as far as bedding, you should make that known to Princess at least 45 days prior to sailing. They will do whatever they can to accomodate him.
Rick
Posts: 3429 | Location: Costa Mesa, California | Registered: November 16, 2006
I'd say that 95% of the time you'll get a decent mattress on Princess but occasionally, as I did on our last Dawn Princess cruise, get a so-so one. If so ask your cabin steward for an egg crate mattress overlay as soon as possible since they don't have that many to give out. They usually solve the problems.