Few days ago just purchased 550c brake pads from Maddriver. He is kind enough to call me and remind me to bed in the pads with 'serious' tone...
Since I changed the discs as well, I noticed to noise and vibration under braking. Initially after installing, the foreman did drove the car and did some heavy braking. When the car was handed back to me, I realised the braking performance was not really what I expected.
Then I continued driving, the brake gradually improved. The improvement was very significant in a short time. After that, I did 5 times 60 km/h - 0 heavy braking, could smell some smoke as maddriver previously mentioned. The brake as a whole showed no sign of fade at all. Managed to brake everytime quickly.
Having drove the car for 4 days already after changing the pads, I noticed if I continued braking like old days, passengers will end up vomitting. Can definitely feel the friction of the pads, under normal driving, everything seems to be more relaxed and easier.
Tested the brakes on highway as well, the tires are not good to grip the tarmac under heavy braking and the tires skidded. Surely the pads bites, but good tires are really essential to unleash the full potential

As maddriver mentioned, the pads will take roughly 2 weeks to bed in. Believe that the braking performance will improve over this week and after I change to a grippier tires.
Really satisfied with the performance of the pads. The friction and the consistency of the braking power really make the car more safe and enjoyable to drive. Will really stick to this product. BUMP to good products!!
Maddriver, when you are free, can you tell me more about the 800c pads? When cold do they work just as well as the 550c pads? The friction coefficient same? What compound are they based? Thanks again.