"and with that large price tag comes almost unlimited tolerance for power second only to the 6-speed"
Wastegate off these forums has broken 3x R154's with an essentially standard 7MGTE.... and Martin Donnon broke his with very little horsepower behind his 1JZ (ignore the claims, people it's nowhere near as powerful as the numbers suggest). I don't think the R154 is really that great... even if it is, it's certainly not 5 times as good as the W58 (despite what the price tag suggests this).