I've got Recon NBS lights on mine and my wifes trucks, also done several friends and many others at work with the same ones. I use the GM harness mentioned by NVRPLZD for all of my the classic body truck installs (just have to flip-flop the wires in the truck end plug for 01-02 trucks), and the Recon harness on all NBS trucks installs. I've never had any problems at all, and the Recon's are cheaper than the GM lights.
I'm a big fan of the NBS lights for sure. I like the fact that the oem gm's are a one piece design, and I feel they're a little better of a product, however to each their own. I've known plenty of guys to run recons and not have any issues.
As far as the install goes, its very easy. The worst part is just measuring out everything to get it perfect and then the unnerving part of drilling holes into your perfectly fine roof. A stiff shot of whiskey beforehand works wonders with this step
I put NBS recons on my 04 that didn't have cab lights and i just made my own wiring harness which wasn't too bad just ran a hot wire and a ground and tied the lights into them then bought a two fuse plug in thing (thats the technical term lol) and plugged it into my trailer light fuse under the hood and grounded to a bolt under the hood. The worst part is drilling the holes if they aren't there already... definitely a lil nerve wrecking lol.
This is a terrible explaination of how i did it lol but hopefully you get the point.