Keeps the chain in place, lightweight and a nice look. The taco is thick and probably handles pretty well hard impacts.
Like every other guide that has range adjustments could be a pain in the arse to install properly. The roller shell just disintegrated after a month of use without notice, screwing my weekend rides. Bolts come loose often aswell. The roller attracts to much debris and it's very hard to clean properly without disassembly of the whole guide.
In my opinion the guide didn't last 10% that it was supposed to last. It's not cheap and the replacement parts could be hard to find depending where you live. Having a part that just breaks without notice is such a bummer, and if there's one thing that pisses me off when riding its when a bike part fails. I definitely will not spend my money again in this kind of guide. There are better options out there.