What they're quoting is a lamp that draws 100w that supposedly puts out 170w worth of light. They usually squirt them full of blue gas that filters the light to make the output whiter too. The only problem is, the whiter the filter is the more of the lamp's supposed output is going to be HEAT, rather than light. The filter agent has to do something with that energy when it catches it , so it radiates it out as heat.

Your wiring harness was designed to operate with 55w lamps. There's some safety margin built in to the design so you can go up a little (maybe 85w, max) but a 100w lamp (almost 200% of the design spec!) is definitely outside the margin of safety.

If you're looking for max light output, HID is the way to go. Look for a 4,700k - 5,000k kit. That color temp is closest to natural sunlight and will give you the best illumination. I personally have a 6,000k kit because I like the slightly blue/purple hue at the edges of the of the beam pattern.

As far as HID kits go, a decent one will run you about $300 on Ebay and will not cause the "bulb out" sensors to get mad at you. Installation is relatively easy as well. I posted a detailed "lessons learned" on this forum a couple of months ago. You can read it here if you're interested.