I have the same one as @poppys and I love it.. I only paid 39.99 for it. really easy to use.. I've had 3 miscarriages previously .. so, got this to ease my mind a little.
I want to get one. but don't have $200 to shell out for one. I have lost five babies out of now seven pregnancies. haven't been able to even hear heartbeat yet and I'm 16 weeks.