The kids got a Wii from my Dad this Xmas. It was great for 2 weeks and then we had a remote problem. Costco is usually a great place to buy stuff, but really supports the Wii poorly. They told us to return it as they would not reserve an incoming unit for us (as an exchange) eventhough it had been purchased there receipt or not. Although I am usually a huge Costco fan, I would recommend buying your Wii elsewhere.
Interestingly enough, a call to Nintendo yielded a request that I smack the remote around to make it work again.