My take on steering head bearings and fork dampeners. Having come from riding bike with screw down dampeners (BSA Victors & HD Sprints) and up to modern dampeners (KTM 300 EXC), I have some thoughts and experiences on the issues facing you and Francine:
Due to your riding styles an expensive fork dampener would be a waste of money and just something else to go tits up on the bikes.
I have had to do maintenance on the state of the art dampeners (mine & others) a couple of times out in the wild. One time the dampener arm dohiggy on the steering head came loose. Sure they works great to reduce fork oscillations, when I am hitting it hard in the whoops & sand at speed. Which neither of you would be doing. Even on my Husaberg 570 FE I have not committed to putting in a Scott Dampener (I have one on the KTM). Before I tightened the FE 570 head stem down it did produce some terrifying head shakes at speed.
Reason: I have tried the 60's approach and just tightened down the head stem nut so that the forks do not swing on their own to the side, but rather creep over. This approach has been working for many years on most of my bikes. Unless you are doing high speed (> 50 mph) sand runs or rough road runs & full lock up slides a lot - a steering dampener is over kill.
As for head bearings going out. Use steel caged one and liberally coat with water proof grease (even a glob in the head tube and when assembled apply a bead of Super Lube (silicon grease) to the bottom gap between head stem & frame head tube. You can also put a piece of snug fitting inner tube around bottom of the head neck to keep dust and water out. Check the slack every month, keeping the assembly tight will ensure the bearings last many years. Carry a drift punch on long rides to tighten down on the stem lock nut till you get the setting right. The original bearings on my 2002 DRZ-400E, are still functioning fine after 17,000 miles. I have had a package of stem bearings on hand for 8 years and never felt the need to install them. Preventative maintenance is the key to keeping a long distance ride operating dependably.