lets face it how long is a piece of string.
the only way to compare both engines is brand new without a single modification.
all this talk about one is better than the other becuase it will hold 1500hp vs 1300hp etc is not a comparrision of anything other than the factory block that has been modified grout filled and so on.
The race to 400kws at the wheels you can't beat the 2j as a cheap single turbo conversion and basic fuel, cooler, ecu tune and clutch. the internals are more than capable of holding this power daily for many years. Some may have valve stem issues over the years but in the scheme of things the cost to replace those is hardly worht mentioning. Obviously there are always exceptions to this where a 2j could have been poorly serviced and thrashed before arriving here, which may blow with a mild boost increase.
An rb is going to require rebuild to maintain 400kws at the wheels which immediately doubles the cost (yes some can complete this in the backyard but reality is most wont or cant) to achieve this goal. it will also require the same fuel etc upgrades. the gear boxes "can" start to have issues (exception of the GTR which has a similar box to supra) which can also increase the costs.
either way they're both equally as good as each other. where one lacks the other pics up. one loves to rev the other not as much. Its comapring apples with oranges.