It's probably too late to be of help to you now - you've probably got your boat!
However, for what it's worth, the Westerly Centaur is very highly thought of here in the UK. They are one of the most popular yachts ever built, you see more of them around than practically any other type.
I have never owned one myself but have sailed them and have had friends who have owned them. They are very seaworthy boats, and sail better to windward than people generally expect a bilge keeler to. There's a surprising amount of room in them and they are generally well built. I think that you need have no qualms about buying one, they're good.