Fortunately, ANA uses a nice thick foam mattress pad that is better than all other first class products I've slept on except for Singapore Suites and JAL First Class and JAL Business Class. It's not exactly memory foam, but is still very comfortable.
I've been sleeping on my California King mattress for 10 plus years and it was feeling too firm, so instead of investing in another mattress which easily can reach a few thousand dollars I decided to try a topper mattress pad. After researching and willing to spend a few hundred bucks on top quality this Extra-plush Double Thick Mattress Pad is top of the line for under $***. The delivery was left at my back door (as requested) and when i took a look at the box it was so big it looked like a mini copper parked there. I didn't even bother to bring in the house and opened the box immediately. It was HUGE I'm happy to say since i put it on the bed and laid down i knew I bought the BEST...It feels like a new bed..thank you...so much!