[cayuse]

Way, the quickest way to get up that short hill is with the 15T sprocket. With the 16T sprocket top speed only goes down, especially when you ride up hills or against the wind. That mod is only good for stretching out the low gears to make them feel more comfortable. The price for that is stretching out the top gear so it's less useful. This is fine if you're riding around in town at 40mph or less, but it detracts from highway riding. Also, Blaine's point on gas mileage will only work for the lower gears, while you are in town at lower speed. At high speeds you'll be limited by the taller gearing, so when you encounter headwinds or hills you'll get worse mileage as you push the bike harder.