I had my xenons adjusted on my S after I lowered the car and they're simply awesome

but i had them adjusted for a different reason.
I had them adjusted as felt they were blinding people and wanted to be sure they were right. But since they were adjusted theyre even better for visibility, but no one flashes me anymore, well not as much as before, so get your dealer to check them out.
Can't comment on old halogen being better/worse than new halogen (I hated the old halogen on my first MINI), but think the new xenons are better having parked my old cooper (with old xenons at the time) and a friends car (with new xenons) next to each other.