I use a MiNewt, originally 150 watt, upgraded to 200 watt when I had to replace the head unit. Now they have 250-350 watts for the same price. Love the nice wide even spread of the beam. I prefer a headlight on the bike and another on my helmet so I can direct light where I want it - into the woods around the bike path to look for animals, around a corner before I turn, at a car to make sure I've been noticed. I have a Vis360 helmet light which provides both a blinking rear and 110 lumen front light. I've very happy pedaling in total darkness with both lights, either light alone is OK if there are streetlights around.
Oil is good, grease is better.
2007 Peter Mooney w/S&S couplers/Terry Butterfly
1993 Bridgestone MB-3/Avocet O2 Air 40W
1980 Columbus Frame with 1970 Campy parts
1954 Raleigh 3-speed/Brooks B72