Even 2 sided high quality bulbs suck. It's merely a matter of the housing they are installed in what detrimental affects the "bulb" creates. Whether it's blinding people, or not shining far enough, or both. There's no universal replacement for halogen that don't suffer these compromises.
Yes, it really depends on the stock output pattern - if it sucks with a halogen, it's going to be even worse with a properly-designed bulb. When my brother was going to buy SL1s for his '01 Century, I first had him check the pattern with the stock bulbs to make sure we weren't going to exacerbate a bad situation. They had a surprisingly decent pattern, so he went ahead and bought them, but they ended up not fitting into the housing, due to how far they sit inside of it.
Any headlight with a terrible pattern to begin with is going to be horrific, even with a good LED bulb. For instance: DS Ram headlights.
Lotta excess light above the cutoff, even with stock bulbs - made much worse by much, much brighter bulbs.
He probably should just put a set of Silverstars in there and call it a day, though we may give the Morimoto 2Stroke 2.0s a shot, because those stand the best chance of fitting (due to the fan design), though it's still not for sure. I know, for sure, that Silverstars will fit. Just don't want them to cause any issues with the wiring, since I know that can happen with brighter halogens (I never had an issue with that in my '98 Cavalier, which ran Silverstars).
Or, we just do something stupid and retrofit it, but I don't think he wants to spend that kind of cash on that, especially with how little anyone is driving at this point in time.
I'd put some more housings and some. HIR bulbs on a relay harness and call it a day in the Century. Would cast same or less than a set of high end LED bulbs
I'd put some more housings and some HIR(yes R) bulbs on a relay harness and call it a day in the Century. Would cast same or less than a set of high end LED bulbs