AKA: My obsession with adding lights to be seen.
Cost is $145.22 on Amazon. 870 lumens.
My Sei Giorni does not have front DRL's. I already converted the indicators to LED.
While you may find cheaper lights, these are very high quality and the only ones I could find which mount easily where they are also easy to wire. No exposed wires and "almost" look stock. I believe they would fit the same on a GTS 300. The mount bolt is on a rubber stem so it flexes if hit. And it will get hit.
The DRL lights run always until you turn on the indicator. Then turn off while the yellow indicator flashes. They have separate white and yellow LED's.
Even in daylight, they are very bright.