Be careful of "flamethrower" lights if you go to Germany, legally you need a light certified for German regulations StVO, which require a cut off above the horizon so it doesn't blind oncoming traffic. Although I'm not sure anybody enforces since all the stuff on eBay and Amazon from China are not certified. And blinking bicycle lights are not allowed.
The German lights are actually great because you really don't get blinded by the other cyclists unless they have the Chinese lights or don't install them correctly and point them above the horizon. The B+M lights are great because they're rechargeable, and can act as power bank for your phone in an emergency, don't sag or change position on the handlebar, fairly bright as advertised.
You can tell if it's German certified by the wavy logo and a certification number embossed somewhere on the plastic body.