From revolutionary to a diluting of classical music, Il Divo have been called all sorts of names.
But one thing is for sure: with 26 million album sales and sell-out world tours, the pop-opera quartet are one of the most successful classical crossover acts since the Italian tenor Andrea Bocelli.
The group are bringing their lush melodies to the UAE on Friday with a performance at the Dubai World Trade Centre.
Il Divo's Swiss tenor Urs Bühler sees the irony in the group being compared with Bocelli.
Recalling his time as an aspiring singer at what was then the Sweelinck Conservatorium in Amsterdam, Bühler says the European classical music community greeted the Italian's mid-1990s rise with some derision.
"He was very successful and, you know, no one expected it," he says. "I remember we were all very snobbish about it, we were just students."
But the British music mogul Simon Cowell had other ideas.
Inspired after listening to Bocelli and Sarah Brightman perform a duet of the Con te partirò , the man responsible for the boy bands One Direction and JLS envisioned a new formation of handsome southern European men singing pop music in an operatic style.
Working as a freelance singer at the time, Bühler didn't think twice about responding to Cowell's casting call in 2003.
While familiar with Cowell's abrasive television style, Bühler explains he wasn't too worried when meeting the producer in his London office, and describes the audition as a rather relaxed affair. "He told me he wasn't interested in classical music. What he wanted was a voice of that quality to sing the songs that he likes and these are pop songs," Buhler says. "I said I am happy to give it a shot if he paid me."
The two-year global scouting process (2001-03) resulted in Bühler joining the French pop singer Sébastien Izambard, the Spanish baritone Carlos Marín and the American David Miller.
With such a breadth of backgrounds the group were able to tackle a wide catalogue of classical and pop music in Spanish, Italian, English and French.
A stirring rendition of Regresa a Mi, a Spanish version of Tony Braxton's Unbreak My Heart on the Oprah Winfrey Show in 2005, heralded their arrival and Il Divo never looked back. Working with ruthless efficiency, the group released six big-selling albums in nearly as many years and have ticked all the boxes, with covers ranging from pop classics (Unchained Melody), Christmas carols (Silent Night) and a few originals (Mama).
However the lucrative earnings and a global following did not keep egos at bay; the early years found the Il Divo camp in turmoil. Bühler says the tensions were exacerbated when the record label forced them to display a fake solid front to maintain the fan base.
"They told us we have to be friends and put us under even more pressure," he says. "That actually made it more harmful than good because we weren't the greatest of friends and we still went to dinner on our own after the studio."
Bühler states he wasn't surprised by the frequent flare-ups; it is what happens when you place four competitive strangers in a room.
"It was an illusion, you can't bring us all into a studio and be friends straight away," he says.
"I think we did pretty well, actually, because most groups who were put together like that do not survive."
Indeed, another Cowell creation, Angelis - think a junior version of Il Divo with British children between 11 and 14 - only managed one album in 2006 before breaking up.
With Il Divo surviving the storm intact, Bühler describes a new sense of calm pervading the group. "I think we trust each other more than we used to," he says. "It is easier to make good music as we now put the quality of the music above our own egos."
The happier atmosphere resulted in Il Divo's latest album, Wicked Game. Released late last year, the sixth album continues their blend of classic pop covers led by the Chris Isaak title track, in addition to Don't Cry for Me Argentina by Andrew Lloyd Webber.
As well as being their best album, Bühler describes Wicked Game as a true representation of the band. "It integrates a lot of classical music but it is still a pop album," he says. "I think it bridges the gap and it shows how far in a classical direction you can take pop songs and still make it have a wide appeal."
Bühler says the song selection for each Il Divo album is solely dependent on musical and vocal arrangements. "First of all, it can't be too wordy or too fast," he says. "Il Divo are about the classical voice and we have to let the words sing, so there is a natural limit to how many words you can pack into that. You've got to have flowing melodies."
Bühler says there were many songs that seemed naturally suited for the group on paper, but tanked in the studio. "We recorded [Aerosmith's] I Don't Want to Miss a Thing for this album and it didn't make it," he says. "It had a beautiful melody, but it didn't have the right arrangements and at the end it was not convincing."
Persuading an enthusiastic fan base of song quality is one thing, but the sceptical classical music community is another. Where before he scoffed at classical music's increasing pop-ification, Bühler now believes groups such as Il Divo are serving as a link between a centuries-old art form and the modern music world.
"A lot of classic tenors are now recording crossover albums as well as arias," he states. "Classical music is hundreds of years old and it feels like going to a museum and it has to move on from that. Maybe crossover is the new classical music for many decades to come."
Il Divo are performing at the Sheikh Rashid Hall, Dubai World Trade Centre on Friday. Doors open at 7pm and the show begins at 9pm. Tickets cost from Dh330 and are available from www.timeouttickets.com