Ive been using my EKO every day at work. So far my experience is this stethoscope can be perfect in hospital/clinic setting. For pre-hospital I would not recommend it. I work in EMS and the EKO does not reduce ambient noise at all. The 911 setting is never quiet place. People yelling, T.Vs are on, radios going off ect...it picks up on all that and amplifies it as well, making it hard to hear lung sounds. It's not like you can tell everyone be quiet on scene so I end up turning the EKO off cause I can actually hear better. Even in the back of the Ambulance you hear the diesel engine more than lung sounds. Gasoline engine does not help either you still pick up engine noise. I'd say it's perfect for home health, nursing homes, and hospitals where it's more quiet. Over all the stethoscope is fine and when turned on the amplification does as intended. Just ambient noise is my only issue.