The Storm swooped on the Fiji-born rugby talent when he was 18, Vunivalu now preparing for a third NRL grand final after debuting at the club just four years ago.

The 24-year-old will head north to Ballymore next year, signing with the Queensland Reds to play in a Super Rugby competition of which the make-up is still to be determined.

In doing so he'll follow in the footsteps of countryman Marika Koroibete - named the Wallabies' best player last year after making the switch from the Storm as Vunivalu arrived on the NRL scene.

Vunivalu confessed leaving the safe haven of the Storm for a new sport at a professional crossroads will be "a bit difficult".

"It's going to be sad; this is where I started my career and it didn't hit me until now, but just really excited to be in another grand final and hopefully do one better (than losses in 2016 and 2018)," he told AAP.

He said a pre-finals pledge with good mate Nelson Asofa-Solomona to cut out video games among other bad habits had set the tone.

"We were trying to be really clean leading up to the finals," Vunivalu said.

"We usually just stay up playing (video game) NBA2K and muck around until midnight, 1am, so we changed that to prepare well, play well.

"And we cut off snacks, especially after games, packets of chips and lollies, that sort of stuff."

Vunivalu will join a fellow Fiji-born winger, in the Wallabies' Filipo Daugunu, at the Reds next season and has been in regular contact with Koroibete.

"One hundred per cent; him being a winger and the Wallabies' best player last year, it's just motivation for me to be like him," Vunivalu said of the Melbourne Rebels' Koroibete.

"I've been messaging him and I'm really excited to be back with him again (in rugby) and will hopefully see him soon."

Australian Associated Press