I'm a little nervous to answer your question because I'm new here and a semi-newbie myself. However, I'm not a total newbie. Putco harnesses are often discussed at a Jeep forum I belong to. Many times I've read the members saying the wires are fine, but the relays are lousy Chinese junk (that can fail and leave you with no headlights while driving down the road. Scary). Many members there buy Putco harnesses and then replace the junk relays with good quality Honda Japanese relays or (if I recall correctly) sometimes with better quality USA or German relays (Bosche maybe?).
However, it seems to me that if a person has to replace the relays, then why buy Putco?
Daniel Stern lighting sells a relay kit with good relays and connectors for a good price (You buy your own wires and wire it yourself). This kit is a good price IMO, but you have to do the work of assembling it, which requires wiring skills and your time.
Stern will can also sell a completely assembled harness with relays (which is what I bought for my 99 Cherokee XJ and 97 Buick Park Ave). His harness is excellent, but spendy.
I think CandlePower.com can also make and sell you a good harness. I don't know the price.
I've also read online that Philips and many other companies also sell good relay harnesses, but I'm not sure if they're the proper length wires.
For a 9006 bulb upgrade, I recommend Philips Xtreme-Vision +100. I've tried that bulb in my 97 Buick Park Ave and it's my favorite. I like it better than two different 9012 bulbs I tried. Though I'm not sure if the 9012 bulbs were authentic or counterfeits since I bought them from Ebay and Amazon and they were not impressive. I think just get 9006 PXV+100 bulb and it's a sure thing and you'll be happy.
If I tried to buy 9012 again, maybe I'd get an authentic one next time, but then I'm concerned my low-beams would blind oncoming cars because 9012 has no shield on the end of the bulb. The 9006 has a shield on end of bulb, which makes it a safe choice for low-beams, and if it's a PXV+100 it's plenty bright and a great color for seeing in all weather.
In my Jeep, I've used Philips Xtreme-Vision +100 and Xtreme-Vision-Plus +130. The PXV+100 are the better bulb because they have better color and better focus, IME. They're also cheaper and often on sale.
For PXV+100, PXVP+130, or any brand 9012 you don't need a relay harness because these bulbs are stock wattage and will give you a good performance boost with your stock wiring. However, a good relay harness will make them 15% to 20% brighter.
