I have experienced both, and I was totally amazed. I drove around in the DOTs in my 98 S70T5 for about a month. They were so much worse than the hybrid implementation that came with my 94 945T that I bought the ecodes for the newer car. The difference was palpable...and especially so after I added the VisionPlus lamps. Aiming is critical to gain maximum effectiveness.

In empirical fashion, I've put my e-code pattern side by side with all the euros (Audi, MB, BMW, Jag) and for pattern quality only the Mercedes is better. The projector system in the Audi scatters too much light, and the BMW doesn't cast the forward light as efficiently as the Volvo (ecode) though it has great side-to-side lighting. The Audi and the BMW, of course, benefit from higher lumen output and higher color temperature, but I think HID's behind Volvo ecodes would be better yet...a terrific lighting package. As it is, I get more light (lumens) focused on the road than a couple late model Audis with HIDs ('00 A6, '01 TT), though their light is whiter in comparision.

The Volvo and the MB share a couple major features: big reflectors, big lenses.
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(98 S70 T5SE misc mods, mostly lighting) (92 940GLE)