I'm sure this has been asked a ton of times but I'm a new grad RN (about 7 months in) working in critical care. I have a Littmann Classic II S.E. that I started nursing school with but I'm a little hard of hearing in one ear & realizing that I'm struggling with lung/heart sounds pretty frequently now. I've heard so many different opinions from coworkers. Still looking for a Littmann but not sure if I should get the Classic III, Cardiology IV or Master Cardiology? Any advice would help!! Thank you!