I'm living in Malaysia and because of the insane road tax pricing for cars above 2.0cc (RM479 for 2.0, RM789 for 2.5cc, RM1000++ for 2.6cc per year) we usually just use RB20det because of the almost affordable road tax, therefore there's lots of RB20det with more than 500hp at the rear wheels, most of them go for the T88 or GT3037 or T04S turbo with standalone ECU with tons of aftermarket parts, achieving high HP is very easy but the problem is, u don't get good response from the turbo (turbo lag), the HP starts climbing after 4500rpm (because the biggest problem with RB20det is the lack of torque), therefore it's just for a moment of fun between 5000rpm until redline. I'll prefer good response with a smaller ball-bearing turbo producing just over 300rwhp (turbo spool from 2500rpm onwards), it's more drivable and more fun when your tail starts to slide. plus the FC isn't so bad. One of my mechanics (who drives a Cefiro A31 with RB20det) has more than 700rwhp using 1000cc injectors and power FC, spent almost RM100,000 on mods alone..........but the car can't be driven everyday because it'll destroy the tires whenever he starts driving........
Sorry i couldn't provide any dyno charts or any proof for this, but anyone who's into RB engines know this is a fact in Malaysia.