It's unique how I perceive the band. Metallica is not as much of a thrash metal band as they are a metal band with a stake in all genres (besides, y'know, black and death). I really like St. Anger. It's a really cool "garage-y" album that shows, in the midst all the risks they'd been taking (Load's cover is semen and blood. Bet you thought it was LAVA), that they're not afraid to experiment. You can't really name any bands that will go to such extreme lengths to innovate besides Metallica. They deserve a better fanbase than what they have, the intolerant, arse-faced, "I-must-criticize-and-hate-all-this-band-releases-to-be-popular" guys.
You can compare the first song they had out to the song that put them in everyone's field of view (I knew about them a whole decade before I even heard a single song about them!), or even something that lost millions of fans for trying, and wrap it up with the warped combination of thrash and heavy metal.
That is effort in maintaining staying power!