100W bulbs are for off road only . . . but as use them as my silvia seems to spend as much time off road (see getting fixed on the driveway) than it does on the road
They were an improvement over the previous bulbs, no problems with them. With higher watt bulbs you tend to get the light pattern diffusing a bit.
If you really want to see at night I recommend having 2 hella rallye 3000 FF's one with pencil beam lens and the other with a driving lens, spot on (no pun intended)
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