I have a car with H4 lamps, I recently replaced a set of burnt out Osram Rallye 70/65 with an extra set of Xtreme Power in my car. Very subjectively, I would say the Osrams are brighter but the the focus is not significantly better. I just got a set of Xtreme Vision and put it in two days ago. Drove it last night, it works well, the light cast right under the cut off in a distance works a lot better. In other words the purported better focus seems to be there, again completely subjective. I need to take the car to a place with beam setter to get it aligned right but so far it's promising
I don't drive at night as much as I did last year so I might just stick to the XV for now.