I think the power outputs in 0.3 are quite different.
My "12 core" big reactors (from a 14 high reactor with a single 12 fuel rod block high "single"control rod to a 3 high reactor with 12 individual control rods) ALL achieve 6.2+KRF/t outputs, and consume about 0.080mb/t. With the powerProductionMultiplier set to 1.0. Oh, when cooled with ender. They have a fuel effiency of 60,000,000 RF per ingot (which takes from 680 to 1000s to burn). That drops to about 25,000,000RF per ingot when water cooled, and rises higher than 80,000,000RF when cryotheum cooled.
My "12 core" big reactors (from a 14 high reactor with a single 12 fuel rod block high "single"control rod to a 3 high reactor with 12 individual control rods) ALL achieve 6.2+KRF/t outputs, and consume about 0.080mb/t. With the powerProductionMultiplier set to 1.0. Oh, when cooled with ender. They have a fuel effiency of 60,000,000 RF per ingot (which takes from 680 to 1000s to burn). That drops to about 25,000,000RF per ingot when water cooled, and rises higher than 80,000,000RF when cryotheum cooled.