Yeah, I've revalved & rebuilt them...all brands are pretty much the same. Not all that difficult to do.
The Bilstein ratings are actually quantified - 255/70 means the rebound force is 2550 newtons at 0.52 m/s; compression force is 700 newtons at 0.52 m/s. I don't know how that compares to anything because as far as I know, no one else rates that way. The higher the number the more 'control' it has = firmer ride.
Generally though, for something that gets rec wheeled, street driven, with an occasional dirt-road jaunt, I wouldn't go as agressive as I did. You won't need as much compression damping and a lighter rebound will only increase the tendency for it to bounce off stuff. Dedicated rock crawling rigs use pretty much the opposite - light compression valving so that the rig sets down nicely onto stuff, and heavier rebound so it doesn't spring back (think throwing a blob of mud at a wall). This is typically the 'stock' setting for many shocks unless you specify something else. Fox usually comes with around 40/80 compression/rebound, each on a scale from 30-90.
Going fast you'll have much larger hits that need to be absorbed quickly, and you need the axle to drop out faster to catch the next bump. Too much rebound and the suspension 'packs' - it doesn't have time to fully extend before the next bump, and over repeated bumps it'll have the same effect as losing uptravel. Then you just bottom out harder. Too little rebound and it'll spring off of stuff; that's where the tuning comes in for your terrain and vehicle weight.
What that means is it's not as nice for trail riding as a 'crawling' valved shock. But that's the tradeoff.
