Thanks Bro, was using mainly bounced/diffused manual flash (I know it is abit wasted for 580EX2) for quite a number of my shots. With all the Aperture/Shutter Speed/ISO/Flash/Focus Section in manual mode, I guess the type of metering (matrix/spot/center/etc) does not matter to me most of the time.
There was some bros asking why do I use mostly M instead of A/S/P, for answer is that it offered me the most control of my shots during a photo shoot rather than leaving the camera to decided for me. Personally, I found this method work well with my Canon 18-200mm IS lens.