Philgoings, I've had Shih Tzu's for the past 20+ yrs
and just got my little Yorkie rescue in January...shes still a puppy 6 1/2 mos old....They are very similar in so many ways, but I think Yorkies have more spunky personalities. My little girl is also much brighter then my little Shih Tzus lol..no offense to them. Both breeds are great because you really dont see dog hair all over the place..I only actually notice that now after almost 2 weeks with an English Bulldog here and there is hair everywhere!! I can't beleive how much a dog with such short hair can shed. One difference I really notice is my Shih Tzus seem to understand that they are little dogs, but my Yorkie has no clue! She has no fear around bigger dogs, which is good and bad. As long as I know the dogs are safe, its a good thing...but, I have to keep an eye on her. All in all I think the mix of both must be such a charming and sweet little baby.
ps....I think I just rescued a little 1 yr old abandoned chihauha, lol. I couldn't stop myself from filling out the paperwork at a Rescue open house....just waiting for my home visit, lol.