I didn't have the issues you did, but I gave up on HID. They were nice and bright, until you were in a fog bank or snowstorm then too bright. They took forever to warm up in cold weather. Replacement bulbs are expensive for the Philips option. I ended up going to
GTR's Ultra2 LED and was impressed. Instant on, last ~20x longer than HID, and much simpler to install. The pattern is full and bright, though not as bright as HID. The only catch was that I had to order replacement dust caps for the headlight because I had drilled the originals for the HID kit.
I'd be skeptical about that LasFit kit. I'm sure heat buildup can be an issue, but I've never heard of anyone on here melting headlights or burning out LEDs because of overheating. The special ventilated cap sounds like a solution to a problem that doesn't occur, and a good method for water intrusion and condensation problems.