I have a B & M with a PWJDM knob. Shifting is quick and precise. I had a buzzing at high RPM that I attributed to the shifter itself but when I replaced the stock knob with this PWJDM one, it is quiet as a little mouse -- a little baby sleeping mouse.
As far as excessive wear on synchros -- hmmm. I had not heard that and the comments to that effect seem quite anecdotal. I have run shrort shifters in many different cars and have not experienced troubling, out of the norm transmission issues.
Like Dr. W Edwards Deming always said: "In God we trust -- all others must use data".