I suppose we are talking all tubeless IRC are what I use ( locally we have mostly roots and muddy banks) edge lasts longer sidewalls softer etc however they are prone to the bead getting knocked off if you riding rocks or if you get a puncture the bead will almost certainly pop off the rim in a very short time.. Dunlops I understand are the tyre of choice for staying on the rim and are e.g the tyre of choice for e.g the scottish, Michelin are a good compromise of the other two. I also wonder how the price of IRC 's doubled...(It is a rheotorical wondering though).