Very mixed reports on the Chinese kits - a lot of them seem to have poor quality bearings etc. If you're going to go that way buy from a supplier with a good returns policy. Britt's suggestion re brushes is a much easier and cheaper way out - even if its your regulator its still way cheaper and less hassle to replace than changing to an alternator.
If you've your heart set on an alternator or need to have one then I'd look for a proper Bosch one and maybe get it refurbed (GSF sell new Bosch, Chinese though but at least its got an identifiable brand...)