Ian ,

French polish is very famous on instrument making and extremelly easy to strach and ruin all the finish.
Even finger nails or acid at your fingers easily deforms it. Best looking polish but if you dont play the guitar or camera but keep it in glass. If you use it at winter , rain , snow demolish all the look and finish.
If summer , wet fingers will ruin it.
If you want a similar look but resistant , use epoxy WEST system Wood Epoxy Saturation System. Cheap everywhere , an distributor in Tuzla Istanbul and all fretless bass guitarists prefers it , it gives all the grain of the wood , penetrate in to pores but without experience its a bigger mess. Its looks like something matte and plastic , soulless.

Another idea is polyurethane finish , more successfull , used in every camera in plastic.

Nitrocellulose is another but flammable.

I think best finish could be linseed or walnut oil , takes time to set but linseed oil have an excellent smell , very freshing. Linseed oil is violin finish grade and easy to repair with the new layer , cheap. Oil paints have it also that all we love the shine.

Umut