[GeeTwo]

So far, we haven't used enough PWM controllers to need any connectors other than the weidmullers built into the RIO, PDP, and PCM. We purchased several of the connectors Omar referenced above. We have only used them so far on test boards (no inter-robot contact), but have had no issues.
In recent years, we have intentionally wired up one or two "hot spare" motor controllers (recently Talon SRs) so that by moving an Anderson pair and changing one character in our RobotMap we could be up and running again. With CAN Talons, you may have to also move the limit and encoder/analog sensors to another controller, but that's still better than rewiring the CAN bus if time is short.
I would only directly solder or crimp the CAN bus of two controllers if I had a big enough budget to keep each robot for many years, and never cannibalize it for parts. If I were to use a crimp or solder connector, I would want a polarized genderless connector (Molex has one out this year for this gauge). Note: Last year, motor controllers with connectors crimped on were considered COTS for build season, but not for the withholding allowance. (compare R12 and R17, particularly as to the a, b, and c bullets - only R12 has a c bullet).