They are probably from Dectane or some chinese replicas.
They cost very much and the quality isn't so good.
On some italian Seat forums users reported moisture into the unit, transparent protective film on the unit start to crack, and other plastic parts tends to crack randomly.
mine are a german make could be dectane im not too sure, iv had them about 6 months and no cracks or breaks on them, and no moisture at all, but my left standard headlight used to get moisture, so id double check your sources mate.
personally i think there worth the money, because they make the car stand out, just depends if you spend to mod your car.
the beam pattern seems like the projection headlights on my Audi, maybe a little less light, but that could be because the Audi has standard xenons which are between 4.5-6k and my seat has 8000k. iv driven it to london and back 400 miles and they were good in the dark.
regardless the beam can be adjusted by using some screws behind the light.