I LOVE my Morkies!! I too was told by my Vet that these mixed breeds tend to have fewer health problems because somehow the "bad" is bred out.
Mine haven't had any problems either. I did buy from a breeder, but I didn't spend a fortune. Probably less than some are selling for one I got two including the "Pet Air". I researched a lot and only found schetchy breeders around my area. They wouldn't let me see the puppies or go to the house...etc. So I found one out of state and have never regretted my decision. The breeder and I still keep in touch.
However, I do understand those that discourage mixed breeding. When I had my Cocker Spaniel, I didn't like seeing a Cocker mix at all. I thought it took away the beauty, but with the back/hip and ear problems...and the dementia he took on...just made me sick.