These have been out for a while now, and several sets are flying. For people with Jabiru heat issues, this seems to really fix the problem. The factory tested a Jabiru 3300 with the LCH setup at full throttle for FOUR HOURS and never got CHTs higher than 230F. Rotec even claims lower fuel burn because you can lean more without overheating (take that one with a big grain of salt). It would definitely take the urgency out of taxiing, which also adds safety as you get time to actually catch any problems before you have to takeoff to avoid overheating.
The full system with water, radiator and piping adds about 16lb from reports, which with the standard 178lb 3300 weight puts the engine just shy of the 200lb FWF weight limit for Sonex aircraft. You could probably shave some weight off this by using a smaller radiator, relocating the battery or other items, etc.
You have to e-mail Rotec for pricing, but the price used to be on their website and I believe it was about $3500. Add the radiator and miscellany and call it $4k. You might recoup some of this by selling your old aircooled heads. Anyway, I think this is a great idea, and I'm glad it's out there. I'd love to hear from anybody who has experience (direct or word of mouth from others) on this product.