ATLANTIC CITY - Ronnie James Dio vs. Ozzy Osbourne. In the world of Black Sabbath, one of heavy metal's most iconic groups, it's a question that divides its legion of fans.

On Saturday night, the Dio version of the group, with co-founders Tony Iommi on guitar and bassist Terrence "Geezer" Butler, along with drummer Vinny Appice, made their Atlantic City debut at the House of Blues under the moniker Heaven & Hell, in tribute to the group's acclaimed 1980 album of the same.

The consensus?

Black Sabbath fans remain torn, although there were definitely more Dio fans than Ozzy fans at the sold-out HOB.

"Dio is so much better, you can't even compare," said Larry Miller, 40, of West Chester, "Ozzy - he's a mess on stage. He's a clown. He throws water on people. The reason they got back together with Dio is because it's all about the music. You always know what you're going to get with Dio: a night of rock."

Anthony D'Agostino, 34, of Atlantic City, agreed: "He has one of the best vocal techniques in rock. He takes the music very seriously; it's not a game. Ozzy gets all (expletive) up. Dio's in a different league."

"No way ... Ozzy is the original," said Rocco Argo, 48, of Upper Darby, Pa. "Dio is an opera singer; Ozzy is a rocker."

Others, like Dennis Stella, 39, of Trenton, didn't care whether Ozzy or Dio was helming the band.

"I'm here for Tony Iommi," he said. "When it comes to Black Sabbath, he was always there, and he always will be. He holds the torch for heavy metal."

Ozzy certainly has his share of supporters, as witnessed by the fans wearing "Blizzard of Oz" and "Diary of a Madman" shirts. After all, he does have time on his side, sticking with the band from 1969 through 1979 and re-teaming with his Sabbath mates for Ozzfest, while Dio was only with the band for approximately three years, before rejoining the band briefly in the early '90s and finally as Heaven & Hell in 2006.

Black Sabbath is celebrating its 40th anniversary this year, but is doing so without its original singer, Osbourne. In fact, the name Black Sabbath is in litigation between Osbourne and its remaining members.

That is hardly the metal spirit.

Trying to remember all of its members is nearly impossible since there are 22 former members of the group. But the Dio-fronted version proved, on Saturday night, the band's final stop on this tour, that it deserved MTV's ranking as the "Greatest Metal Band" of all time.

Dio, who has made a name for himself as a solo artist and leader of Rainbow, still possesses an amazing voice. He can still hit every note he ever sang on any of his albums with Black Sabbath or otherwise.

The band played songs from its four studio albums with Dio: "Heaven & Hell," "Mob Rules," "Dehumanizer" and "The Devil You Know," released earlier this year. Fans looking for "Paranoid," "War Pigs" and "Iron Man" would have to look elsewhere. This was Dio's Black Sabbath. This was for the grown-ups.

Opening with the musical intro "E5150," Heaven & Hell ripped into "The Mob Rules" before unleashing "Children of the Sea," "I," "Bible Black," "Time Machine," "Fear," "Falling Off the Edge of the World" and later fan favorites such as "Heaven and Hell" and "Die Young."

While Dio's vocals and great storytelling were the highlights, Iommi's fine fretwork and Butler's thumping bass provided the soul for Dio's dark lyrical poetry. After 40 years, and Iommi and Butler's combined age of 121, it's amazing that they can still rock this hard. Black Sabbath - Dio is 67 - proves youth does not matter; talent does.

Equally impressive was Appice, whose drum solo was that rare drum solo that was actually entertaining. With so many drums and cymbals, Appice actually stood up to play some of his kit, just so he could reach it easily. The crowd was appreciative.

In and out of the band every few years, Dio is like the hot mistress that tempts the band into fling after memorable fling, even if they do ultimately go back to their wife.

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