I've had a couple of wood handled Semogues. None of them ever suffered any negative effects to the finish but I did not soak the handle of the brush. I think as long as the handle is sealed and finished properly, and you don't soak the handle, you shouldn't have any problems. If your handles are painted, like some Semgues, dropping the brush could chip the paint, but dropping a resin handled brush could chip the handle itself.
TOFLAC-U, AOM, LEMS/ Stay back! I have a Merkur, and I know how to use it!