While in middle and high school, Leong was selected for principal positions playing both Cello & Trombone in the California All State Jazz and classical ensembles, the Monterey Jazz Festival All Star Big Band which toured Japan & California and the National Grammy High School All Star Big Band which performed at the 1997 & 1998 Grammy Awards Events with Boyz II Men and on NBC's nationally televised Today Show.

At the age of 17, Leong and the Grammy Ensemble also performed for the Presidential Summit for Anti-Violence at Philadelphia Constitution Hall, where Presidents Bill Clinton, George Bush Sr., Ronald Reagan, Jimmy Carter, Ford and Secretary General Colin Powell signed the country's first anti-gun act affecting schools nationwide.

After moving to New York, while studying Jazz Trombone and Orchestral Cello at the Manhattan School of Music on a full scholarship, he continued to perform and produce with many well known musicians from the Jazz, Latin and Hip-Hop worlds such as Marc Anthony, Huey Dunbar, Horace Silver, Ryuichi Sakamoto, DJ Qbert, DJ A-Trak, Chat Hugo, Harry Belafonte, Christian McBride, The Mingus Big Band, Wynton Marsalis & the Jazz at Lincoln Center Orchestra, Balkan Beat Box, Keali'i Reichel, Firewater, Chick Correa, Lila Downs, Lionel Hampton, Dave Douglas, David Taylor, Steve Coleman, Eddie Palmieri, Henry Threadgill, Claudia Acuña, Fermin Muguruza, Lew Soloff, Jason Lindner, Tony Escapa, Miguel Zenon, Dafnis Prieto, Yosvany Terry, Christian Howes and Paquito D'Rivera whom with Leong collaborated on the "Panamericana Suite" Album, which won two Grammy Awards for "Best Latin Jazz Album" and "Best Classical Composition" in 2011.

[2] He invited DJ Qbert to join him in performing and giving interactive lecture demonstrations on the history of Hip-Hop to show musical collaboration methods as examples for world leaders to follow.

He joins fellow musicians Pharrell Williams, Will.I.Am, John Legend, Bono, and Michael Jackson alongside business leaders such as Jack Ma, Mark Zuckerberg, and Hugo Barra in a community geared towards activating positive global change.

[citation needed] Leong is an advisory board member to The Wellbeing Project[9] which creates wellness programs to promote smart and healthy ways to work.