This tool is a great way to correctly tighten torque sensitive parts. I like the multi size bits the come with the product. Some other similar tools only come with 1 end size. My only issue is that ritchey could have made the handle a little more comfortable to turn.
Changed carbon seatpost & needed to tighten to proper torque spec. Originally bought similar Bontrager tool from LBS. Didn't realize it was 4 mm (1 size only) and I need 5 mm. This has 4 interchangeable bits. Each bit is stamped with it's size (4, 5, T-20, etc.) so you don't have to guess. Loosens as well as tightens. Haven't used it long enough to know about durability, or I might have given it 5 stars. Glad I bought it. Works great. You need one.