SP Dynamo is well known among lighting nuts as the "less expensive Schmidt." Heck, we'll admit that they also look exactly like the Schmidt, and the reviews seem to indicate that they have the same durability. While we certainly believe in the power of brands, we also feel that we sell function before we sell a company its logo. SP Dynamo is used by several our staff (with great accolades) and are very low friction, very light weight, and the ability to turn all friction off when the light is off. A huge upgrade over the much heavier, high friction Shimano options on the market.