Obviouisly your wealth of experience speaking here, many people have run over 330rwkw for extended periods. Its all in the components being used, and the quality of the fuel/tune.
And the deck height, you would have to deck the block too much to get the correct height. Rb25 pistons seem to crack at about the same power level as rb26's ie about 350rwkw without knock.
Turbo outlet temps can get up to 300 degrees. bear in mind cubes is making over 300rwkw with stock 2inch r32 intercooler piping, so it cant be that restrictive at stockish power levels.
i think you are a bit confused, a tune doesnt last a certain time, its not like it wears out. I wouldnt have any problems with gt tuning my car, if i wasnt tuning it myself.
Im not certain, although it is in theory possible if you reconfigure the vacuum hose layout, and fit needed restrictors, although without a map sensor, i cant see there being accurate closed loop boost control, as different airflows make different boost with different Intake temps.
Prone to cracking? More info please, RIPS 8 second stock bottom end seems to differ. The only part of the rb30 "prone" to cracking is the oil pump, and thats if you use something other than an rb30 pump.
For $8700, i would be wanting a high end oil pump.IMO its the first place you should spend the money on an rb bottom end(although i didn't)
Are you absolutely certain that the bank doesn't have the records, as im pretty sure they keep them for more than the required 7 years. If you are going to get a solicitor, you may not need him to go to court, just send a few letters with an official letterhead and see what happens.
Idle issues are usually caused by dirty aac valve, the throttle body could probably do with a clean also, as could the AFM with some carby cleaner. I would also check trouble codes, and check tps adjustment.
Not quite sure where you got your information from, but the only difference in the galleries is where the vct feed is,. Rb25 has 11mm head bolts, when rb26 has 12mm
Pretty sure this has been covered a few times before, and the conclusion is that although in theory there are pros and cons for either way, there is no real world difference between before and after, just make sure it is plumbed back.