If you want a quality light that will last, try Lupine. They are a German company, and make lights for the German market. I have a Piko 3, bought in 2011. It is still working perfectly on the original battery. It is small, powerful, and most importantly, the beam is properly focused.

They offer a Piko R on their German site, but I am not sure if it is allowed for on road bike use, they duo offer it for off road use. They have other lights specific for on road bike use on the site.

The Piko was expensive, but well worth it for me. I rarely run it at full brightness, it lights the road well on low and medium. It works great, and after eight years, it is still working with no issues. I used it this year on a two week tour and never had to recharge. I did use it, but not a lot. The last night of the tour though, I used it for over an hour, that was after light use over the two weeks. The battery holds a charge very well.

https://www.lupine.de/products/bike-lights