This CD is just a compilation of singles that JLS have already released and is designed to make people pay again for the same old rubbish. It will probably sell, not due to any musical talent contained therein, but due to JLS's fanbase consisting mostly of silly hysterical screaming schoolgirls who will buy anything they release (until some other x-factor rubbish comes along in couple of years time, then they'll buy that instead).
JLS do little more than sing in whiny girl-like voices and prance about to cheap prerecorded backing tracks created by some producer playing with a drum machine, chanting tacky lyrics such as "put your hands up, everybody in love". They couldn't even play a tambourine between them, let alone a proper instrument such as drums, guitar or bass, etc.
JLS are not a band, they're a karaoke act.