There isn't so much a "best" place for sunset, but more of what you want to look for, and how you look out for it. Even around the urban areas, HDB estates, outlying parts of Singapore, there are lots of good moments. Its whether you grabbed the chance.
(It is also not about the camera/lens, but how you make do with what you have)
No best timing...but be there early to check out the surrounding and composition, prepare your equipments etc..and sometimes the sky after the sun has gone down is even nicer than when the sun was still up.. so hang around after sunset for a while.. =)