I added on mine. Changing the bulbs, it's not that hard on your integra but some folks have problems because they don't have the right screw-driver for the little cover. If I remember correctly the cover is held on with a security torx screw.
If you go with a set of HID's the HIGHEST color temp that I would go with is around 6000K. The higher the temperature, the less light you will get with automotive HID's. Once you get to the purple ones in the 10K range you have the same amount of light as with a regular halogen bulb!
As far as brand and quality, it is VERY true that you get what you pay for. Cheaper HID bulbs will fail prematurely, run hotter (risk melting things and starting fires) and will have a low light output vs. better bulbs. As well some cheap bulbs can rattle around and move slightly while driving causing other issues.
I personally would get the OSRAM CBI 5000K HID lights. They are some of the brightest bulbs on the market and as well are 5000K with no loss of light output over 4300K bulbs. The second bulb I would suggest is the Philips 81522+ bulbs. They are 4300K but they are a bit brighter than the stock bulbs.
You should check what HID Kit they provide and then you can tell if it's cheap or not.