I also have a Littmann Cardiology III, and I also LOVE it. I can't hear anything out of other 'scopes compared to mine! I bought mine when I was an EMT student, road noise makes breath sounds even harder to hear, but with mine I can hear just fine while driving. The other day I even heard a murmur that my instructor couldn't hear with the cheap stethoscope he had with him! If it wouldn't have annoyed him, I probably would have handed mine to him and asked him to try listening through it. But, it would have annoyed him so I didn't.
The drawback to the Littmann Cardiology III is it's price, but I looked at it as an investment. Hopefully, it will last a long time and pay for itself.
I bought mine from www.steeles.com
, I bought it on Saturday and had it delivered on Tuesday! They had the cheapest prices that I could find, right now the Littmann Cardiology III is $122.99.