We stayed at Cha Am (close to Hua Hin) at Christmas and visited Hua Hin a couple of times during our trip.
The beach there was OK, pretty busy (specially compared with Cha Am) but probably not as bad as Shek O in summer
I wouldn't really call it a "quality beach" though - there's too many people to really relax and the sand wasn't as nice as, say, other parts of Thailand. You can hire horses, jetskies, banana boats etc so there's horse poo and noise + diesel. Wasn't too bad for a stroll in the afternoon though
There are loads of restaurants, some good (we had great Italian on Christmas Day) some bad and they even have Burger King and Starbucks if that's your thing
The seafood wasn't too bad around there either! And of course cheap shopping, there's quite a good night market.
It wasn't really my scene but there was plenty to do and it IS handy to Bangkok. Pick a good hotel and relax by the pool if you end up hating the beach
PS - Cha Am was quieter and the beach was nicer.