Awwwwwww just like every other person that's rides a Burton you get all butthurt, because burton makes the best boards ever yea right.
lol. I think they make as good a snowboard as almost any other company. I think they have a pretty great warranty program. I have a ton of snowboards, from many other companies. I ride quite a bit, and have ridden a LOT of boards. I have boards from 4 awesome companies in my quiver right now. I'd consider Burton to be one of them.
OP: Channel boards with EST bindings do feel pretty great. EST definitely feels a bit more responsive, and I prefer the way the board flexes under my foot. Hard to explain, but I would say get yourself a set of Cartels, or Malavitas.
If you don't go that route, Call C3, see if they have the updated discs. I almost wonder if those are the old discs, not meant for the M6 hardware. The M6 inserts that you have should extend upwards into the disc and lock into the holes provided. That should be what is preventing the slippage. If the M6 inserts do not fit fairly snugly in each individual hole, I would just call C3, and get these