I bought Philips X-treme +100% because they won the AutoExpress test. They were about 20GBP a pair but were an absolute nightmare to fit. My hands are just too big and I had to get my girlfriend to actually fit them.
I got them because my previous car (E39 540) had Xenons and I was hoping for something similar from the uprated bulbs. TBH, I was underwhelmed as the difference is only just noticeable.
They are probably just about worth the money but not the hassle.