I've used marus' lights before and there very nice, great quality, very decent fit, what I would recommend really.
I've also done a set of the umnitza lightwurkz ones from ebay and honestly they look a little more finished and all especially when there off because they have a clear cover over the leds, so instead of seeing many small leds you just see a real ring that looks much more like the rings of the bmw's, BUT and this is a big BUT, the plastic housing they use makes the rings too big to really fit in the damn headlight and the rings will contact the headlight lens, causing spider cracks in the lens at this contact point once you fully assemble the light... I ruined a set of lenses finding this out the hard way, to use them you MUST make spacers to space the bezel back, away from the lens... really sucks that they give you no indication of this, sucks to have to eat a set of headlights just to correct this, hope this might help someone else from making the same mistake...