So the HID plasma arc produces heat differently than the halogen bulbs, and tends to burn and put out heat in one direction instead of in a sphere pattern.
Going 55watt also shortens the lifespan of bulbs by quite a bit, while gaining you around 15% more INTENSITY, not brightness. Intensity means the light will look physically stronger on the ground, but the trade off isn't worth it just in my opinion. Plus I would rather not have to buy another 650 to 550 $ housing lol.