Well there's a lot of people running Type-Rs at 1kW daily but it sounds like they got really good unit on a good batch. It's probably not the case of each Type-Rs out there and I don't really want to take another chance, pay ~$200 w/ shipping and/or taxes and burn it again.
Type-X sounds like a great option, as the 2 others you mentionned ($160 shipped, I guess it's in US only). There are still 2 questions that you guys haven't answered. First, the 2 and 4 ohms thing (as my amp outputs the same thing at both 2 and 4 ohms, what is better in general of the electrical system?). The second question... my PDX with a 1 farad cap has been running in my Yaris without really any problem with the gain set to half. But is there any major long-term impact of such a big build on the stock factory Yaris hatchback alt and/or electrical system? I don't want to blow everything away and I don't want to change everything. So if it may have bad impact on the future of the car, I prefer selling this amp for a M6 or PDX 600 and then look for a Type-R or any other decent 500-600W 12" subwoofer.