I haven't had too much experience with the electronic stethoscopes, but from what I've heard, they're not all that great. Some of them give you a lot of background noise so really I found that older attendings (probably with prebycussis) tend to like them.
I personally prefer the littmann cardiology master series, but the cardiology III scopes are good too. My friend really likes the Welch Allen triple head scope. I find it a bit cumbersome to roll up into your pocket.
But that being said, as a resident I don't think you need a really fancy stethoscope until you're sure you're going into a field that's going to be needing it. My friend bought a Littmann master cardiology and ended up going into radiology... it's probably collecting dust now.😉