I would also recommend the Davis Equipment over the OS Stuff. (WRM200)
Have been using OS Stuff since the end of December, and already ad some problems with the Wireless Signal.
The Temperature Radiation Shield isn't very good.
I've since got a second hand Davis VP1, and that seems much more accurate in every way.
Just need to get the data logger set-up, and I can star posting data to my website from there, instead of the OSstation.