The second kit is digital and is (reportedly) a preferred type. I have those on mine, while we have analog on the Pathfinder. I really don't notice much of a difference, but think about it - analog or digital? Not really much of a choice - go digital.
6ks FTMFW!
You will love them I have them on mine and it is 100% better than stock halogens... But in all honesty the 6k and 8k is all about preferance my friend has 8ks on his Tundra and they are about the same as my 6k's..
Don't cheap out with an eBay kit that's $35, you'll get what you pay for. OEM HID bulbs whether d2s/r are 4300-4500k. I wouldn't go anything above 6500k personally due to light output and reasons other that blue or blue/purple light output is just ridiculous looking and dangerous. If you're uninformed or ignorant or are into the whole rice boy thing, I guess it's okay. Lol
I wouldn't recommend putting an HID kit in your reflector housing headlights. Get a good pair of projector headlamps to do correct. I've seen some okay-tasteful projector lights out there for your car. The bulbs in any kit you get are going to basically be a d2s design, which are not meant for reflector housings. = lots of light refraction in unwanted direction & dangerous to other drivers on the road.
Any route you go, make sure you get a harness equipped with a relay and fuse. Of you don't know how relays work or how to wire it up, have someone who knows do the install. gl
35 watt in my car. I think that's enough for clear lenses, but I have a friend with pretty dark smoked headlight lenses that went with the 55 watt kit, and it looks pretty similar to mine as far as light output goes.