I too installed the Lux H8 160 in my X5, and I just received a second set for my M3. They are definitely the best option for those of us with the non LED corona rings in our E70s.
You can't increase the wattage of just the outer ring because its one bulb that lights both rings, strictly through light refraction. So, the best options are upgrading to the full LED headlights (for those with X6 or X5M/X6M) or get the Lux H8 160 bulbs and not worrying about it anymore... Option 1 is about $4000, option 2 is $200. I went with Option 2, and I'm over it past that!
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2018 F15 X5d Carbon Black/Nutmeg Individual- Oil Burner Tow Rig
2013 E82 1M3 Carbon Black/Black- S65/DCT Track Toy
2013 F25 X3 35i Alpine White/Chestnut- German American Family Hauler
Past: '11 E91 335is, '11 E90 M3, '10 X5M, '14 328d, '03 330i Dinan3 ZHP, '04 330i ZHP, '12 X3 35i