The first one I bought was off e-bay. It was an old medical machine. I think I paid $5000 for it. It has had some problems and getting parts has been very expensive and hard since it is an old maching.
I got set up to bring in the Ultrasound set up for veterinary use now and selling them for $2700 with the foot pedal. I like the smaller unit better since it is portable. The Sloans bought one and Robert Sieb, and the guy from reptile radio also got one.
As for what it has done for us. Knowing when the female is in her prime time, and when she is done, helps me put the males in when they are needed. I waste less time guessing and more time knowing.