I tried Michelin S12XC, labeled as "soft" but on the Michelin off road tire chart they are shown as soft/intermediate. I found that the traction was outstandingly good, but unfortunately they wore very quickly on the rocky terrain of Calabogie. The wear was quite evident after just a few rides. I would not recommend them for our area because of this. I am about to install Michelin M12XC, labeled as "intermediate", but shown as intermediate/hard on the Michelin off-road tire chart. These were highly recommended to me by a top level rider.
Michelins are high performance and a bit expensive, however. I have heard that Kenda Washougal intermediate gives good performance at a more accessible price. Maxxis are also good value for the money.
There are lots of other good tires out there from Dunlop, Pirelli, Bridgestone and other companies, and other people may well have had good experience with different models. I think that you are on the right track with intermediate because the terrain at the locations you have mentioned includes sand, mud, loose dirt, hard pack and rocks. I prefer intermediate/hard because I would rather trade off some traction than have to change tires several times a season.
There is general agreement that heavy duty inner tubes are recommended to minimize the chance of pinch flats.
If you have any money left, a knobby knife can extend the useful life of your tires, I have one and it works;
http://www.knobbyknife.com/ (please note that I am not in any connected with this company!)
Colin
