There were plenty of reasons to be skeptical of this Guns N' Roses reunion tour.

Would there be any passion onstage or would it be a rote musical exercise with the dangling carrot of a meaty paycheck?

Could Axl Rose, a guy who admittedly joined the Bloated Aging Rock Star Club a few years ago, handle the physical and vocal rigors of a stadium show?

And, would the band notorious for starting their concerts after even Madonna has gone to bed actually show up?

The suspicion of any doubters was quickly quashed Wednesday night at the Georgia Dome when Guns N' Roses – the heyday lineup of Rose, guitarist Slash and bassist Duff McKagan, along with longtime accomplices Dizzy Reed on keyboards, Richard Fortus on guitar and Frank Ferrer on drums and newcomer Melissa Reese on synthesizers – launched into the opener "It's So Easy" and the crowd roared as Slash stepped forward for his first solo.

By the way, this all started at 9:30 p.m. – 15 minutes earlier than scheduled – and ended more than two and half hours and a few thousand damaged eardrums later.

The big news of the tour? Axl and Slash together again. Photo: Katarina Benzova

From that first song, Rose proved a vital presence. Clad in ripped jeans with a flannel shirt tied around his waist and what turned out to be a series of T-shirts – likely due to the perpetual sweat that dripped from his elbows throughout the show – Rose slid from his pronounced nasal delivery during a taut, funky “Mr. Brownstone” to the mighty wails that infuse “Welcome to the Jungle” with its primal intensity.

The arrival of that song – the band’s first major hit from 1987 – was everything a fan could anticipate. While Rose’s vocals were a bit rushed on the verses, his yowling was in admirable form, as was the beautiful cacophony created by McKagan (who showcased a Prince symbol on his bass) and Ferrer during the song’s famous breakdown.

Performing on a stage stacked with tiers of stairs and flanked by a pair of colossal video screens, Rose and Slash in particular consumed the open space.

Slash struck his classic pose of right knee tipped forward as he melted strings during a solo on “Double Talkin’ Jive,” while Rose raced around the stage and spun on one leg as pyro popped behind him during “Live and Let Die,” the band’s rather thrilling cover of the Wings staple.

Watching how Guns N’ Roses appeared to legitimately enjoy playing together – was that a smile on Rose’s face during the epic “Civil War”? – you had to shake your head thinking about all of the years wasted on acrimony and bitterness when they could have been rousing fans and stuffing their bank accounts.

But at least they wised up in time – and came ready to play as professionals.

No one would have begrudged Rose if he had to take a hit off of an oxygen tank, but between these shows and his stint with AC/DC (he'll be back with the Aussies Sept. 1 at Philips Arena), the mercurial frontman seems, at 54, re-conditioned for rock 'n' roll.

Rose did cede the microphone to McKagan, who churned out a boisterous cover of Iggy and the Stooges’ “Raw Power,” but he otherwise rarely rested, whether complementing Ferrer’s locomotive drumming on “You Could Be Mine” with a sneer or delivering “Sweet Child O’ Mine” with nostalgic flair.

Slash kept the 40,000-plus in attendance from flocking to the beer lines with a riveting rendition of “Speak Softly Love,” otherwise known as the love theme from “The Godfather” as well as a gorgeous guitar duet with Fortus on Pink Floyd’s “Wish You Were Here,” which was full of fretboard acrobatics.

Axl Rose still has his rock star moves. Photo: Katarina Benzova

While Guns N’ Roses achieved their mega-platinum fame with a combination of serrated guitars married to insinuating melodies, the band could also stomp out a power ballad with the same intensity as one of Rose’s glass-shattering shrieks.

That ability was on display early in the night during “Estranged,” from “Use Your Illusion II,” and later during the pensive “November Rain.”

Seated at a piano brought to the edge of the stage, Rose, with Slash nearby, unfurled the timeless coda of “Layla” as the introduction to “Rain.” As Rose dug deeper into the sweeping 1992 hit, he sounded like a man who believed what he was singing.

Fans likely chuckled when they heard that Guns N’ Roses christened the tour “Not in This Lifetime.” But not too long ago, the notion of hearing “Patience” or “Paradise City” with three of the band’s five original members seemed preposterous.

But a combination of clarity and maturity is apparently a musical jackpot.

Opening the Atlanta date was The Cult, the venerable British punk-goth-rockers.

Singer Ian Astbury was a vision in black – including sunglasses – as he and the band slammed through "Lil Devil," the dark and foreboding "Deeply Ordered Chaos" and "Sweet Soul Sister," with its reverberating chorus.

Astbury’s vocals often echoed uncomfortably in the half-filled stadium, and, despite his neck-vein-popping vocal performance on “Fire Woman,” the song was audibly mucky. The tunefulness of “She Sells Sanctuary” was better discerned and by the time they wrapped with “Love Removal Machine,” Astbury’s hair was freed from its ponytail and the crowd was primed for the main event.