Georgia Nott of internationally famous Broods believed the duo would not have made it if it wasn't for a leg-up from the competition.
"Rockquest was pretty much what made this happen for us," she said. "People are watching and listening for what comes out of the competition and we were lucky enough to meet Joel Little and our manager Ashley Page through it.
"We seriously would not be in the amazing position we are in right now if Rockquest didn't exist. It was and always will be one of the best things we ever did."
Opshop frontman Jason Kerrison also paid tribute to the contest.
"Opshop came about because we met in the most fertile environment you can imagine, up against the most competitive bands you can imagine," he said. "Smokefreerockquest puts a support network around you and that makes the difference."
Kimbra became a household name after singing on the 2012 multi-platinum single Somebody That I Used to Know by Gotye.
But it would never have happened if she hadn't had help from the competition when she was a struggling young solo singer in Hamilton.
"I love that Smokefreerockquest gives kids a real incentive to pick up an instrument and write a song," she said "It often gives birth to a real passion and musicianship from a really young age.
"I was 14 when I placed second in the national final and it was the perfect kind of encouragement to push me to keep at it."
Powered by national musical instrument chain Rockshop, Smokefreerockquest has prizes including $22,000 in Rockshop vouchers.
There is also a $20,000 NZ On Air recording, video and promo package, a 'Decent Exposure' campaign on The Edge TV, a photo shoot and branding package from Imaginary Friends.
Tonight's finalists include six bands - Alien Weaponry, Oh Boy!, Daffodils, Half Eaten Pie, Ah Jeez and Retrospect. Solo artists are Sonatane Kaufusi, Cam Dawson and Iris G.
Smokefreerockquest judge Simon Martin is also Kimbra's musical director. He believed the top acts all had an originality of vision.
"For New Zealand music to make an impact both at home and overseas, we need to cultivate a unique identity, and the artists we picked really showed a strong sense of that, no matter the genre," he said.
"For us, they represented a bright future for creativity in New Zealand music."
