Mentawais any good in December or January?

I'm looking for info about whether the Mentawais are worth a trip in the off-season. Thinking either a land camp or boat. Does anyone have any recommendations on where to stay or charter boats and also what the surf would be like on average please? I've been there before in February but think I was really lucky as we scored Rifles, A-frames and Macaronis. Just looking for info as it's a long and expensive haul from Scotland. Thanks