To get a figure for power is very hard - as it depends on the tuning and what other power adders were added to the 20R/22R hybrid.
As you probably picked up in the articles - the 20R head flows better than the 22R head. What that means for power depends on how you use that extra flow. Power gains can be as little as no gain to as much as 15-25HP at the flywheel high revs. The 22R engines are known to be torque producers, the 20R engines for howerpower producers - kind of counterintuitive since the 20R has a slightly longer stroke to bore, the 22R having a larger bore to stroke - but that what it turnes out to be. Better to say with a freer flowing head - other modifications. like forced induction or bigger cams will help produce more power (engine has more tuning potential). A 22R bottom end with a 20R head, turbocharged/intercooled (CT26 turbo from a Supra), fuel management, and boosted to 25PSI - runs about 350HP.