I have heard a wide array of headphones and IEM's. I find this to be a very fun hobby to fuel my love my music. Generally, there is the mindset that the more you spend, the better it is. Well, that is true to an extent. The reason I'm saying this is because I honestly think the HP50 is one of the best headphones that my ears have had the pleasure of listening to. I've heard the Sennheiser HD 800, HD 650, JH13 Pro, Westone ES5 and a few other top tier headphones or IEM's and though they all sounded draw droppingly amazing; they don't incorporate all of the traits and characteristics that the HP50 possesses.
The Sennheiser HD 800 and HD 650 are both power hungry beasts that require a beefy amplifier. Also, they're not ideal for portable use because of their open back nature and required power output. The JH13 Pro and Westone ES5 are both highly portable and block out a ton of noise but their sound is not as coherent and spacious as the HP50 which is also a portable headphone. The HP50 to my ears are just as strikingly clear and accurate as the top headphones that I have heard. Unless you need a super expansive soundstage, then there isn't much more those headphones have to offer other than costing more money to maintain.
Comfort wise, these are great. Zero comfort issues for me. My ears are small anyways and actually found them able to fit inside the Sennheiser Momentum without any comfort issues. The V-Moda Crossfade M-100 with stock pads however was highly uncomfortable for me until I threw on the XL pads. The HP50 is a very light headphone with a premium finish and look. I am very happy with the physical construction of this headphone.