Any thoughts on the general quality of work to be expected from each retipper and/or the merits of each choice of stylus would be most appreciated.
Frogman
Peter at Soundsmith has retipped two cartridges for me. Both came back in good shape. One of the cartridges I considered "nuding". They were adamant against doing this due to the microscopic metal particles floating around during vinyl play which would be attracted to the cartridge. With that said if I send him another one - one day, it will be with instructions - "as close as possible to stock." Re-tip only.
I figure if you like the cartridge get it retipped as this keeps it as close to stock as possible - assuming the cantilever is good. If there is something you would like improved you can gamble with a different cantilever. I would call Peter or the other providers and ask how the sound and general operation (.i.e, less or more VTA changes) will be affected with the different materials/diamonds. Remembering that this will be based on "their system/s" not yours.
Soundsmith usually does not retip. They replace the stock cantilever and stylus with a new assembly including a ruby cantilever.
They do retip only - but it does need to be requested in advance. A number of cantilever materials available. There is more info here.
Soundsmith FAQ
I would also recommend Axle in Germany but from last word on the forums he has become very busy, and there is more complicated logistics with the big pond between him and yourself.
my two cents. Good luck
Cheers