I think the OP may have been referring to halogen projector lamps with halos. My recommendation: don't bother.
I had the VW Golf Helix/Depo halogen projectors with halos. I was thinking the low beam output would be better with the ECE beam pattern. I was wrong - it was dramatically dimmer than stock. I ran several types of super-bright halogen bulb. No difference. I also ran H7 HID retrofits (I know, I know, but at least it was in a projector housing with a cut-off) and this wasn't much better. I returned to stock about a year ago and the difference was night and day.
The high beams were also noticeably weaker, and I ran extra driving lights mounted to aluminum flat stock bolted beneath the upper grille in the winter with these lights. Since moving back to stock, I haven't felt the need for the driving lights.
The halos themselves were a dim and dull warm white and the little incandescent bulbs burnt out very quickly. Access to these bulbs was very difficult. The sockets all friction-fit in around the circumference of the halo, which is quite far and around tight corners from the actual access hatches at the back of the lights. It's not a job for people with either short fingers or sausage fingers, and the housings have to be removed and placed face-down on a workbench, which means dropping the bumper (something else I got good at doing with these lights)
The plastic housing was also very brittle, and the clip for one high-beam access hatch broke off during one of my many bulb swaps. The extra depth of the projectors means the rear covers are deeper than stock, and on the left side this runs afoul of the air intake cover. A new cover was provided with the bulbs, but it didn't fit either. There also wasn't enough clearance between the cover and the factory air intake to actually *open* the hatch to access the low beam, signal, and fog bulbs. The bumper had to be dropped every time a bulb blew.
The only "bright spot", as it were, was the fog lamps. I put yellow H3 bulbs in the fog projectors, and they were quite useful. I was stuck in thick thick fog a few times with these and switching off the main lamps and running only yellow fogs was very helpful in seeing through the soup (though everyone else felt the need to flash me, because dude, your headlights are off, eh).
