Couldn’t disagree more about the VVT-i. If you went back 10 years then aftermarket parts, support and mapping would have been more difficult, however technology has progressed and that isn’t the case anymore.
Finding info might be a little harder for the 1JZ VVT-i but I wouldn’t be put off by it. The VVT-i is a great engine.
Lots of people are running the 2JZ VVT-i engines mapped on aftermarket ECU’s without a problem. Camshafts are readily available as are internals should you want to go the whole hog.
As mentioned above, drop James (http://www.mkivsupra.net/vbb/showthread.php?347614-Performance-Hart) a pm. He will know more than most.