If you do mostly town riding you might be ok with the stock lights. I do a lot of riding on dark country roads so I needed the HIDs.
Prices for HID kits vary tremendously depending on the brand. This isn't an endorsement of his products -- I've never bought from him -- but this guy's been active in the Vendor forum.
http://www.advrider.com/forums/showthread.php?t=309439
http://www.futurevisionhid.com/singl...-21_22_31.html