Used a Reflex helmet mirror. It was ok and did the job needed. Then came winter along with bad cellphone talking CA motorist. Almost got swipe on a few occasion. I also needed some extra light when I noticed that car did not see me well in area such as merging on a city street with car comming out of freeway off ramps, so I ended up with a white and red mini blinkies lights on my helmet next to a P7. Helmet looked like somethinng from a Sci Fi film and it got so bulky that I felt like a bobble head. The lights also affected my vision caused from reflection. So then I took off the Reflex and went with Mirrycle on my roadie with STI and a Blackburn handle mirror on the MTB set up as a commuter. Both type of mirror has it good and bads but it all depends on your application and set up.