On my good bike, I've got an 04' WTB Laser V w/ Ti Rails.
I couldn't stand my stock seat, so I ditched it for something that looked better, felt more comfy, and was lighter.
On my crappy bike I have a POS trek seat... the leather's half gone and the foam is falling out.. but it's still comfy.. and I don't care about how this one looks.. so it's staying on there for a while.
-Matt