first of all I am no Cyclocross rider but I think you are still the only one who know much about Cantilever brakes.
I have a XT-Brake form 1996 (BR-M737) and I need new pads.
There are two different versions of pads:
1. Pads like KoolStop Eagle, Swissstop RAT, ...
2. Cartidge systems like Fibrax, Trickstuff, ... In this case the pads are changeable and you have to use V-Brabe pads.
What are the best pads for a Cantilever brake ?