The tracks were all passable in a 4x4.
They were straightforward, generally wide, often rocky, with just a few mildly difficult bits. Varying gradients. Great scenery.
No major effort was required i.e. no need to dismount and push. This was with a light luggage load.
We were one 640LC4-E, one 640Adv and one BMW R1150GS. The BMW rider dropped out after a few days (can't remember why - little or no off-tarmac experience? The need to conserve the bike for his onward trip to Africa?) after a heroic effort.
The route was more or less from the Med to the Atlantic sides, with just the first few kms in France, the rest in Spain.
I'd allow some time to do the whole lot - we got as far as the Andorra region in 4 or 5 days but then we weren't rushing.
Bad part was a mad rush to catch the ferry home from Roscoff. If I did the trip again, I'd arrive and depart mainland Europe from one of the ports in northern Spain.
If you ride from say, Santander, to the Med to start the trail ride, the sealed road on the French side (not the motorway) is a great ride in itself.
I recall the cost of the roadbook was around 70 to 80 Euros. Well worth it IMHO. It came in a book which we cut up into a rollchart. You'll need some sort of holder for it (I have an RB-TT) and an accurate tripmeter that reads in km. There were also GPS points in the roadbook that were helpful when we got lost. I also found using the roadbook took some familiarisation (despite having used other ones, but in a different format, in the past).
You can find some pics of the trip on Geoff van de Merwe's website.
PS Perhaps this reply belongs in the route planning or Europe forums.
[This message has been edited by Ian (edited 15 February 2006).]