As of yesterday, Meze 99 Classics. I can finally hear stuff properly and I can wear them for hours. They replaced the Koss PortaPro as my default headphones.

Other than that, Sennheiser HD 4.40BT which have served me well for the last four years and Sennheiser HD 599 which have no redeeming qualities to them whatsoever.

For completeness I should mention Sony WI-C200. Great for conference calls, not suitable for music IMO.