Arc fault and shared neutrals

2 Arc Faults, AFAIK, cannot be used on a MWBC.

If your panel is a Cutller Hammer CH style, not BR style you may be in luck. They have 2 pole afci breakers for that panel. I don't know if they are combination style however which is required for all new installations since the begining of 2008, per the 2005 nec. Also since it is a 2 pole breaker, both of the circuits would have to naturaly be afci protected. That is the only way I know of multiwire branch circuit wiring to work with ark fault technology. Good luck in your new adventure fishing in new cables.

ge,siemens and cutler hammer br all have 2 pole afci breakers to use in this situation

I have been using single pole AFCIs because I'm sure they work and I haven't been trying to use them on old MWBCs. Rewire!

Has anybody used the two pole AFCIs and are they working okay on MWBCs?

yes the cutler hammer and siemens work fine but the ge's have been terrible

Thanks!