Many members here got their HIDs from Xenon Depot. Also many believed that a more expensive kit is better in terms of quality which is generally true. But I got my kit from DDM Tuning for $29 + shipping. And until now its still alive..no flicker.
I don't know what to believe anymore, German Technology, European parts, China, Taiwan, new chip, blah..blah slim ballast,philips technology, heavy duty, warranty,US seller, Hong Kong factory, Quality guarantied..
LOL! when they look and have the same output, while some have really bad kits.
Choose a seller which replies fast to your inquiries and can be contacted easily through email, chat or call. It means they have better customer service. And its best to buy this time because fall/winter they are super busy with shipping.
One thing, installing HID in a 2004 with halogen reflector will cause much glare to the opposite traffic(I have tried that). You might want to do a HID projector retrofit. Though you have white bright low beam, it will look more aftermarket because of the glare.