I know you asked for current students, but having spent 10 years in a paramedic career using and owning stethoscopes I figure I can safely weight in. I swore by the Cardiology III and Master Cardiology as IMO they worked the best in noisy situations, like on a chaotic accident scenes, in industrial buildings and most importantly in the back of a diesel-powered ambulance. This was important for me as my hearing is far from perfect. I never had problems distinguishing lung sounds, heart sounds or hearing a blood pressure with these scopes, but my mileage varied extensively with other types. I especially hate cheap Sprague style scopes (the ones with two tubes) because you can get a ton of tube sounds.
I would, however, wait until you hear what you need for your school. Some schools, I have heard, even supply them. It would be a shame to shell out a lot of cash on a new scope just to have the school provide reasonably decent ones.