HELP!!! Best top-quality stethoscope for physician?

My husband is debating about which stethoscope he should get- he's a physician getting ready to take his PACES in two weeks (in which he will be specifically listening for even the most minute murmur), and needs the best quality stethoscope he can get. Of course, he already has a stethoscope (a basic Sprague model), which is OK, but not great. He doesn't hear any better out of my Littman II SE, and isn't impressed with the Littman Master Cardiology (which is what the majority of his colleagues use). He likes the Littman 3000, mainly because he can increase the volume and focus on the sound, but the problem is that the proctors of the exam make using electronic stethoscopes a bit difficult. Any suggestions? Cost is not really an option (well, unless it exceeds around $500), as we want the best quality. Any advice would be welcome.

Apparently, he needs to be able to hear grade II diastolic murmurs, like subtle MS and AR, and to differentiate MR, VSD, HOCM and TR.

I'm extremely surprised he isn't happy with the Littman Master Cardiology.. I've heard only the best about that one. Well, anyway-go to the 3M website and you can compare the different Littman stethoscopes. In my opinion, Littmans are always the best..

Wow, if the Littman Cardiology scope doesn't fit the bill, I don't know what will. All of the doc's at my hospital either use the II SE or the Cardio. The rest is how you use your ears!