Biewers and Yorkies are both wonderful breeds. I have both, and can't say one bad thing about either!! My Yorkie is the quietest out of the three, lol. When the Biewers start playing, they make noise
My female Yorkie has more 'tude, than my female Biewer, but my female Biewer does have 'tude, just not as much as my Yorkie
They get along great, they are well behaved, smart, inquisitive, nosy (lol), eager to please and FUNNY!!! And most of all, extremely loving and attached to their human mommy (me)
Their personalities are very similar, I would just say that my Biewers are more humble than my Yorkie