Picked up a cheap X-Fusion O2 rear shock as a spare for my 2 year old Zesty. Does anyone have any experience of using/servicing these shocks? Is there anything like the Fox Float service kit around so you can do it yourself?

I’ve also been thinking about the Vengeance as a a fork upgrade sometime in the future. Price and reviews are good but spares/support and home servicing are all v.important too.

Thoughts and links appreciated…