I'm running one of my Alfines and my im9 on ATF. The Alfine (same guts as my high end Nexus) shifts even better, I'm sure it will have better cold weather performance, last winter when it hit -18*F here my Alfine had the factory grease still. Shifted fine, a little slow. The Alfine/Nexus is easy to service, just pull the guts and soak. im9 has disposable dust cap on drive side, need a new one to pull the guts, nobody sells the dust cap yet...for that hub I removed the non-drive side con and poured a couple tablespoons of ATF into it.