Silverstars are good, especially the H4 bulbs used in the Monster. They don't look cheesy, and are actually considerably brighter. But they don't last very long, expect a season or so before they burn out.
Avoid CoolBlues, they are just regular halogen with blue tint added so they actually produce less light, and they look stupid. How many Hyundais do you see running around with them? Nuff said.
True HID kits draw around 35W, as opposed to 55W for a standard halogen. They also cost a lot and require some effort to install. Amperage change won't make much difference in a modern bike, but it is useful in an old Duc with substandard single-phase charging.
I'd personally stick to Silverstars, HID is a lot of money and trouble for looks alone.