Lots of Ista dogs on their site... as I personally know Greg Larson of Isa Shih Tzus... I'd say this breeder is a pretty good bet! It looks like this breeder works closely with Greg's lines, and I can say that Greg has some of the best Shih Tzu temperaments in the Midwest.
Thumbs up from over here!
PS - funny story about Greg and Ista Shih Tzus... Greg had a top winning bitch named Bikini. I believe she won Group at either Westminster or some other large televised show, and Sada calls me up all excited, and hurriedly tells me about the win and asks if I wanted to see a photo of "Greg in a bikini"... or, that's what I thought she said!!! I started laughing and told her NO, I didn't particularly want to see Greg parading around in a bikini.