If you have MKIII's, just get these.
I used to have to take breaks after wearing my T50RP's for more then a few hours due to a pressure point on top of my head. Very glad I decided to grab this as it makes them so much more comfortable. Incredibly easy to install, even to someone who has never modded headphones before, such as myself. I only wish I could get something like this for some other headphones, such as the M1060, but I digress.
If you have a spare 20 and have a RP series headphone, do yourself a favor and get this.