I got a large, and I've only gone through about 1/4th of the syringe over the last 6 months. I've only used that much because I used it on many of my puzzles. I would like to say that you should avoid using it on bigger cubes because it actually makes them slower and in order to get the puzzle to feel even on all sides you have to use a fairly large amount. Use CRC or any other spray lubricant on bigger puzzles. As for how long it lasts, it should last you at least 6 months at the very least. It kind of depends how you lube your puzzles. For example, if you lube the mechanism a lot and you pop the cube a lot; obviously you'll be losing a little lube every time you pop it. If you were to ignore this fact, Lubix lasts for an extremely long time.
