What to look for usually is where the kit is made, Germany, Korea, or Japan are the ones you usually want to get, but not everyone provides that type of information if you are trying to compare, especially the ones off of ebay.
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HID XENON CONVERSION KIT 3000K 4300K 6000K 6500K 8000K so you should head over to them if you want an HID kit that's dependable, I've also heard KLight was also a good brand, it's up to you.
I bought from a company that wasn't well known, for $200, a little more expensive and so I thought the company was good, not like the $99 ones on ebay. Now that company is just gone and I got screwed, so now I'm currently doing a retrofit with Customlightz instead, I for one and sick of aftermarket lights and am going back to OEM.
You should have a very safe bet in xenondepot, as a lot of the 8thcivic members on here that have PnP HID kits probably bought from them.