I also use Rock n Roll Gold luber, it is $7.99 at my LBS. Before we started doing mountain biking a bottle would last 6+ months on our 2 road bikes and 2 commuter bikes. We don't have winter weather and only have about 60 rainy days a year so I don't deal with much muck on my road bike. Now that we mountain bike it is closer to a bottle a month.
Amanda
2011 Specialized Epic Comp 29er | Specialized Phenom | "Marie Laveau"
2007 Cannondale Synapse Carbon Road | Selle Italia Lady Gel Flow | "Miranda"
You don't have to be great to get started, but you do have to get started to be great. -Lee J. Colan