My headphone collection is a bit more modest than it used to be, but my favorite open air headphones that I've owned were my Sennheiser HD600's, and my favorite closed/canal phones were my Etymotic ER4S and ER4P. I don't listen to as much music as I used to, so I make do with lesser models now.
I have those exact same choices...there is a man who knows his quality!!! BTW, Etymotic finally came out with a new prototype extrememly comfortable excellent dB insulating foam that I have been testing for them over the last 2 months. I can wear them many hours, day after day, with no ear soreness. None of their other Etymotic sizes worked ideally for me, or gave great sound isolation, and I had started using the
M-Audio IE-30's for comfort...but now the Ety's are the best by far.
Especially for air travel, the noise cancelling HP's are a joke compared to these....and I finally have Ety's that I can use endlessly. I don't hear the stewardess, or the airplane engines. When going for walks, I don't hear cars going by, or dogs barking....so I have to stay alert. With these new Etymotic ER-4P (or 4S converter),
I feel like I finally found the Holy Grail of acoustic Nirvana. They have not yet released these new tips for retail sale yet.
For casual light weight listening/workouts, I use the
Sony MDR-A44L that has surprisingly good sound and folds up nicely.
I have never tried the new
Shure SE420 or SE530, and they are likely very great, but when I used the E-5c, did not like the fit, isolation, long term comfort, despite the superb bass they produced.