Ever since talking to a part time BMW tech instructor, who also owns his own shop, I've been using his recommendation of Lithium grease in a spray can. You can buy it at any hardware store for about $4-5. After using it for about a year and a half now, I've noticed the chain picks up less dirt and grime than normal chain lubes, even ones like Maxima chain wax. This chain has also lasted longer than the 2 previous chains on the bike. I'm at 20,000 miles with this one. The previous 2 lasted 17,000 miles each.
