Took around three or four hours. With a thicker thread it would be a lot faster. It's just for looks but it may theoretically strengthen it a bit, since the plastic is pretty thin. The earpads are the Brainwavz 100mm Round Sheepskin. Wouldn't buy them on my own since I don't necessarily think they're worth their price (since they're only marginally more comfortable than the stock earpads) but I got them as a gift from family. I also used to have some rubber kitty ears on top, but I got worried that the constant pressure would eventually damage those flimsy plastic tubes so I took them off.
I think it's great when people make off the shelf stuff their own :)