Talking specifically only of Z32 headlight glass: Although I've seen photos online of what you're talking about, I really wonder if that has more to do with installation error. I have seen some pretty good cut offs with very minimal distortion on retrofits with the Z32 headlight glass. Sure a headlight lens without the fluting is probably better but in my opinion the Z32 fluting doesn't make for all that bad of light output at all - whether Halogen or Xenon based. A clean set of projectors will go a long way as well.
Further, I have OEM Xenon's and they use the same headlight glass as Halogen JDM headlights - as was mentioned prior. I modified mine for LHD but still the cut off is clean and I've never really noticed any distortion. Here's a photo of mine against a wall.
Re: distortion from the headlight glass is the real issue - 
