Real leather is the only one that will last the longest. Gentle wipe-down after every use, and moisturise twice a year, you can expect it to last. You'd likely be selling the headphone off with the leather ear-pads you had on even after 10 years.

They are a premium product. Sennheiser Momentum if I'm not mistaken does come with genuine leather earpads. There are plenty of manufacturers of genuine leather replacement earpads, but headphone manufacturers themselves seem to be a bit more reserved when using genuine leather.

I have a regular fake leather that lasted for over 2 years now (Superlux HD681 Evo), and no sign of quitting. High quality fake leather like those that come with the higher end Audio Technicas I've seen people looking for replacements after 5 years or so.

This post has been edited by VagueConcerns: Apr 19 2017, 11:55 PM