If you're listing Ung Hoang Phuc as best singer ... you've heard nothing of Viet music yet . Try listen to:
Đàm Vĩnh Hưng ... his best soundtrack are : Anh Vẫn Biết, Góc Phố Rêu Xanh, Lạc Mất Mùa Xuân, Say Tình, Vùng Trời Bình Yên, & Tình Ơi Xin Ngủ Yên (Vietnamese version of the song Hold Me For A While - Rednex)
Nguyễn Thắng ... Vì Sao Không Nói, Người Ra Đi, & Vầng Trăng Xưa & Xin Cho Mãi Yêu (one of my favorite)
Jimmy Nguyễn ... Nhớ Về Em, Tình Xưa Nghĩa Cũ, Tình Trong Cơn Mưa, & Ngồi Đây Vẫn Mong Đợi
And if your gf cheat on you, got married, or just straigh out unlucky in love ... you would really appreciate music sung by
Trường Vũ ... Tôi Mất Người Yêu, Tuý Ca, Được Tin Em Lấy Chồng, Yêu Làm Chi ... practically all his soundtrack

2 . However, I advice you not to listen to him too much if you're ... 7Ti`nh, it would make you wish you find the nearest building to jump from if nothing else does

... and that's just some of the male singers ...

2 after all that quick search, I just realize the topic is Bands ...

so far ... haven't find any Viet bands that can compete with other international bands ... they end up so like copycat of other countries bands
-bncat
Source : www.vietlove.com (they got over 5000 Viet songs all direct dl)