I put mine in today and am pretty happy. General impressions as I said before are that they're quite well built. Everything feels solid and sturdy. There are good water-seals on all the connectors and all the connectors fit together quite well.
One odd thing is that you have to reverse the connector from SVX's lighting connector to the ballast because the wires are backwards. Fine fit backwards just fine and I used zip ties to hold them together instead of the built in clip,
The lamp itself fits sungly into the socket on the headlight housing. The lamp appears to be pretty well built. The envelopes were identical and appeared to have the same amounts of metal-salts in them (as best as you can tell by a visual inspection)
I fired them up and they came right on. There was a small warmup delay, but it wasn't really bad, and that has to do with the amount of Xenon gas in the envelope. As with any other Metal-Halide lamp that I've seen (I work with lots of them in the professional lighting world, just much bigger 500-1500W
) the initial startup included some colored flickering as the salts began to evaporate and take over for the Xenon gas. That should be less prevalent once they've had a little bit of burn-in time.
I haven't been able to take the car out because of some other problems, but so far they seem so good. DDM also makes a big deal about their lifetime warranty on the whole schebang. So if they do go out DDM should replace them for you.