All right I listened to all 3 of them.
I still think TE is better... but not by much. Yes, Junior's Eyes, Johnny Blade, Air Dance and the last track are good, but some of the others (like Shock Wave) are just dull and uninspiring.
Heaven and Hell is brilliant. (which I knew anyway)
Mob Rules... what a difference a few years makes. When I first heard it I thought it sucked except for Country Girl and Turn Up the Night. Now it's entirely the opposite. I really wouldn't think of it and H&H as 'one' album though - H&H is far meatier.
So I hereby retract my earlier comments and brandish all my hate at St. Anger, because I'd forgotten that piece of shit exist. Ashamed is too light a word for what Metallica ought to feel about it.