I have had a Fournales shock absorber fitted on my R100GS for now 18,000 miles/29,000km (I ride this bike in the USA).
Of course if I let the bike in the garage for 6 months the shock absorber will loose some pressure (I was surprised to have a R100GS turned into a low rider, checked the air pressure and found 6 bars instead of the + 19 bars recommended.
I choosed this brand as I can adjust both the spring rate and the ride height when altering the air pressure. And when switching from riding the bike solo to riding with a passenger, for a short ride for exemple, I can make a quick adjusment with a push/pull button, even if of course I can fine tune the pressure for a longer ride. I have a second R100GSGS, fitted with an Ohlins, that I am riding currently in South America: the spring rate, which fits a for a single rider, doesn't work very well with passenger and lugages, as I can only alter the ride height.
But I would never ride with a Fournales without a pump, especially on longer trips: Fournales sells a tiny one which weights next to nothing. This pump allows you to make adjustments according to the load of the bike and to the road. It allows you to refill the absorber in case of a loss of air (this loss is not sudden from my experience, and from what I can understand in other´s experience). It allows you to check if there is a loss of pressure (remember that if you fill to 19 bars for exemple and want to make a check five minutes later with the manometer on the pump, as some air will go into the hose between the valve and the manometer you will only find 17.5 bars for exemple, nothing to panic about).
One problem is I don't know if there is a dealer or somebody who can work on these shock absorbers in the USA or Canada. Any answer?
Hope it helps.