I bought my Sherpa frame used, the previous owner told me that he had a frame builder cut off the clamp, paint it and then he put on a Salsa brand clamp. If it was me, I would have spent several careful hours with a hacksaw and file instead of paying someone, but I have pretty good tool skills. That said, you don't need much skill to use a hacksaw, but you need some skill to make it look nice in the end. The key is to not be in a hurry and be very very patient.
My nomad has the original clamp, I have not had any reason to change it. But, I wanted to be able to remove the bolt if it broke, so I cut a slot in the bolt so that I can use a slotted screwdriver in the bolt to remove that half of it if it breaks.
I used to carry a spare seatpost bolt, but I figured out that my stem cap bolt will substitute, so stopped carrying one.
I would not want to come out of a store and find my seatpost and Brooks Conquest has gone walk-about. Thus, I do not recommend a quick release. On one tour where I had heard that there may be a few areas where theft could be a concern, I used a thin gauge steel cable between my saddle and a cantilever brake bolt as an extra precaution against saddle loss.
Good luck.
