Pork,
It literally takes 5 minutes to install, no different than changing the headlight bulb. The part # is 73273-11 and it lists for $399.95 (subtract the 20% from one of the on-line discount dealers and it's only $320). The larger 7" version does cost more. As to fitting with the windshield, it fits in the stock headlight housing so no worries there.
One thing I did notice about the light output that I like is not just the quantity but the quality. Anyone who has switched to HID's will know that it's not just more light but where and how it throws it that makes them special. There is a dark twitchy piece of road along one of my favorite local runs that is under construction. It has lanes shifting over and back again and lots of steel grate and cracks that are patched with tar. It used to be hard to distinguish where you needed to be and all those shiny tar patches in the crack repairs made the surface conditions hard to judge (it's right by the ocean and damp more often than not). So that is the first place I rode after installing the light to see how it did on a tough road. The improvement in visibility was so much better that I never thought about the $$ again.
Look it's not a miracle light just an alternative to HID's for those that want a much brighter, whiter and more focused light that draws less power is really simple to install. There are a few very minor downsides. Besides the cost it's heavy and that weight is all at the front of the headlight. On the ConV the nacelle is soft mounted so when you are at idle that weight hanging out in front shows up as slight jitter at the stoplights but disappears once you are rolling. It's no big deal but worth mentioning. Also, it's not a "traditional" HD look so some may mistake you for a non HD when you are coming at them. If you care about not getting an occasional wave from a fellow rider that will only give the nod to another HD, then stick with a traditional light.
For me I have seen the

light and there's no going back to the dark side.
MikeV