It really depends on what the warranty covers the availability of prompt service in your area should something go wrong. Some extended warranties cover maintenance items like cleaning, for example (but I'm not sure how much this would actually benefit a tapeless camera).
Also, what are you going to be using the camera for? If you plan on editing on a Mac, HDV is a lot easier to deal and will typically yield better results. Most hard drive cameras are AVCHD-based, which Apple doesn't support natively. It has to be converted into AIC first (which is a slow process and takes up a LOT of space), which kind of defeats the purpose of having a tapeless camera in the first place.
The Canon HV20/HV30 (HDV codec on MiniDV tape) are much better cameras in your price range, IMHO.