Rory Gallagher.
Gary Moore is an excellent guitarist, technically better than Rory, I think. But Rory has an 'honesty' in his playing, something that comes from the heart. I know who I would rather have seen live.
I remember when Gary started doing his blues thing. Being at the time a stalwart hard rock fan, I thought he'd sold out lol. But then I picked up on blues, and then I didn't like Moore for what I perceived as a cynical attempt to ingratiate himself into that world by having people like Albert Collins and Albert King play on his records - I thought he was just trying to make them look bad with technical superiority. But blues isn't about that. And I thought it was just a passing fad for Moore.
I'm more sanguine about it these days. I like Gary's blues stuff, but wish I had copies of his earlier rock albums that were better produced too.
Rory? Well, I never had such doubts with him. He just delivered everything straight from the heart.