I went with the Aveo Powerburst system, bought from Aircraft Spruce. I have not tried them yet so I can't comment on brightness but I love the fact they're small, light, and nearly indestructible.
In order to run wires, when I was installing the forward ribs I enlarged the aft tooling holes (closest to the spar) with a unibit so that I could put some rubber grommets in the holes. I then ran a few strings through the grommets, taped the ends to the main spar, and finished the wings. After everything was installed I taped the wires (can't remember the gauge, but I followed the light instructions. Maybe 18 or 20 gauge) to the string and pulled the wires through the grommets. If I were going to do it again I would just run the wires instead of strings.
Once I fit the wingtips I used a whole saw to cut out an opening in the wingtip and then used nut plates to make the mounts removable if needed. I can't remember where I got the mounts but someone makes them for Sonex wingtips and I think they're around $25ish.
As I said, I would certainly go with LEDs now that they're so cheap and they never burn out, and I would also run wires in your ribs now before you install the skins. Some have ran wires in the aft ribs but I went with the front ribs and am glad I did.