Happy Birthday - I would go for one without arms. Also before you send him out take time to go try some of the chairs - it won't help if he gets you one that isn't comfortable to you. I use (ok everyone can laugh at me) the bunge chair from the container store and several of my friends have used it for a day and loved it. But make sure that whatever he is going to get you works for you. We wouldn't be happy if DH told us he wanted a wrench and we get to the store and find that there are a zillion choices.