Thanks for inspiring further reading folks, I had heard about the mechanics behind closed and open cartridges, but didn't know the practical differences. Found some good reading here
on the racetech site and here
on another site. I think most people go for open cartridges on these bikes because they are not meant for or planning on doing pro circuit motocross on a beemer
, and open cartridges are more durable (but that's from my reading just now, I really have no experience in the matter).
If you're worried about air gap, you could always install a set of air chambers for tunability and balance between forks. I saw at least one guy do this with the WP50s. Mo money tho. And as long as you're throwing money around, you might as well take it to a professional suspension guy for a few bucks. I do however plan on doing as much research into it as possible to try and learn it myself.