Unfortunately they are far from being neutral just like other wood arms. They are more like instruments than tonearms. Wood is a ringing material especially on the frequencies we hear. If you like the sound of your tonearms none of the above really matters but they certainly have a significant sound signature.
Reviving this old thread as the OP, the wide assortment of tonearms people use with their Koetsu cartridges tells me there are no clear winners in this cartridge-tonearm match-up although the FR 64s/66s, Ikeda 407 and Glanz were mentioned most often.
I've narrowed my personal choices down to a Fidelity Research 66s and a Glanz MH-1200s. I find them both attractive, well-made and both have received excellent reports in the field. I wanted to ask if anyone has had the opportunity to compare an original Fidelity Research FR-66s to the Glanz MH-1200s tonearm specifically when used with a Koetsu? The FR-66s is of course the older arm and would possibly require some maintenance (bearings and wiring). For almost the same money, a new Glanz would be ready to go. A secondary question is how does the FR-66s compare with its little brother, the FR-64s which is about 1/3 the price?
In the end, the Glanz MH-1200S won out over the Fidelity Research FR-66S. The ease of buying a new off-the-shelf item was the deciding factor. In addition, one of the knocks against the Glanz had been its lack of azimuth adjustment, at least in the MH-124S. This shortcoming has been addressed in the 1200S as there is now a "tilt adjustment screw" which is located at the end of the arm tube and allows for fine azimuth tuning. Thanks to all who offered their experience and expertise.
Previously, some Glanz users have opted to substitute other headshells which have a built-in azimuth adjustment. The Arche headshell is frequently mentioned. Has anyone compared the performance of the stock Glanz headshell with the Arche or other brands of headshells?