http://i314.photobucket.com/albums/l...age0088888.gif
Going round in circles!!!LOL
What happened to the OP? Hopefully she is still here.
Personally, I would go for a Biewer and not a parti yorkie. The Biewer is trying very hard to become AkC registered and they do have a written standard. They are different from the parti yorkie, a separate breed. These Biewer breeders, the reputable one that is, are doing all of the health testing and are breeding to their written standard.
On the other hand, the parti yorkie, is not being bred to the YTCA or any other Yorkie standard. This color annomoly is a fault and just like an underbite, should not be purposely bred for. The parti color, amoung others, will never be recognized by the YTCA and there-fore they will never be shown in conformation. The parti breeders claim that there have been many DNa tests done, especially on one kennel, to prove that they are purebred. The only thing that these DNA tests did was to say that the parents of the puppies were in fact the parents of the puppies. This test cant tell you if these puppies are purebred yorkies and cant tell you if there was another breed introduced in an earlier generation. Like the Biewer, the parti yorkie is most likely the result of a yorkie being crossed with another breed to bring in the parti gene. In the past, it was VERY easy to falsify AKC papers, so it would be easy to add another breed and claim that they were purebred yorkies. This is the only reason that AKC has to register these color faults.
But with any breed of dog, you must do your research and look at several breeders and pick one you are comfortable with. There are alot of bad breeders(greeders) out there in every breed. Reputable breeders will only breed to the written standard of that breed.
Best of luck finding your puppy!