I found that the problem with uprating your mains (or using additional driving lights) is the difference in total brightness between main and dipped beams. When you have to dip for oncoming traffic on an unlit road, you're plunged into darkness.

The SEAT leons have poor lights primarily due to low adjustment. Move them up and gets some uprated bulbs and the difference is marked. I have 80W driving beams and 100W main beams. As long as they are adjusted correctly, makes a big difference. Only thing you got to watch for is the headlamp switch which can burnout due to the increased power running through it.

I am wary of 100w bulbs; I had a pair in the main beam of a 3 series BMW some years ago. They were really bright and lit up the road well, too much so on large M-way reflect road signs that dazzled me! I didn't use them too often (roads in the south-east are either lit or have too much traffic) but when I sold the car and tried to take the bulbs out for my next car - they had seized in. I guess they had got TOO hot.

These days I have PIAA Extreme white that "draw 55w and produce 100w", plus they are E marked and legal. Best bulbs I've used.