pulse > probe
pulse starts are easier on the bulbs and offer greater lifespans on the bulbs because of it. They also help with firing higher kelvin rated bulbs: 14000k.
however, I have a probe start 175w and have no quirks with it, other than it doesn't like 20000k bulbs. (only on a 25gal so whipdee) I have m80 (250w hqi) on my main tank
