After several days of research on Speed/light head Badminton Racket, I have decided to go for Yonex-Nanoflare, which is less confusing than Li Ning & Victor.
Nanoflare has 4 main 'active' series, namely 1000, 800, 700 and Nextage, with Nextage being the cheapest version. Each series has 4 grades- Pro, Tour, Game and Play respectively. Pro is most stiff and Play is most flexible. "Play" grade is about RM 300 and "Game" Grade is RM 459. The Pro grade is made in Japan, Tour & Game grade are made in Taiwan and the Play grade is made in China.