I would say Birds of Fire rocks the hardest. One of the most influential jazz fusion albums of all time.
This reminds me of how I got into the Dixie Dregs years ago and reading interviews with Steve Morse and seeing the Dregs live. You could tell that they were heavily influenced by the Mahavishnu Orchestra. John McLaughlin has always been very disciplined and the compositional structures were complex but beautiful and fearsome at the same time!
But you say that Inner Mounting Flame rocks even harder? Now I'm going to have to re-listen to this one again.