MK pads will take around 500 km to break-in.
Honda recommends only those brake pads that you buy from the dealership. Car manufacturers source parts for different companies for different cars, and even in different countries. An example is the Corolla EE100, they have an entire page of the owner's manual dedicated to stock replacement spark plugs, which goes like: In Thailand, Denso ABCDEFG model, In Pakistan NGK ABCDEFG, in Japan Denso PQRSTUV etc.
Also, your pads faded because they had worn out. It means the heat capacity had lessened and pads were rising to a higher temperature for the same amount of friction.
I think your Honda City is the EXi S. Means third gen facelift. If so, the factory fitted brake pads are Sumitomo M9226 FE (made in Japan). These are manufactured by Advics Co., Ltd. Physically, the back plate is green coated. I'm not sure about the material, but it has copper filings. It did not look anything like NAO (polymer resin) or leather. Unfortunately, the Advics website does not have an online product catalog.
Actually, Sumitomo is a Japanese industrial conglomerate just like Mitsubishi. Sometime in the past Advics acquired an 80% stake in Sumiden Brake S & E, Inc. (the company which made Sumitomo brand brake pads) from Sumitomo Electrical Industries Ltd., a part of Sumitomo group and now all Sumitomo brake business is done by Advics and has no relation at all with Sumitomo tyres etc. Advics has been very actively acquiring other other brake-business companies in the past few years. I have reason to believe the same item could be found by all three names:
- Advics M9226 FE
- Selp M9226 FE
- Sumitomo M9226 FE
Also, HAMP D9603 is the Honda rebadge/rebrand/remark for Sumitomo M9226. (HAMP is Honda brand name presumably for Honda AutoMotive Parts, just like Toyota they give parts in their own packing). So the same thing can also be available by this name.
(Companies do this type of things due to many reasons, including tax-saving and brand management).
I asked about the mouse-shape City pads just in case your Honda City is fourth gen. They are JB NF92 FF manufactured by JBT (Japan Brake Industrial Co., Ltd.) in Thailand. (They could also bear the name JBT NF92 FF). This page verifies that JBT indeed has a subsidiary and other interests in Thailand. Sadly, the JBT website also lacks an online catalog.
Don't know much about the actual friction material of NF92 FF. It seems semi-metallic to me. This is because it had lots of steel but no copper filings. Also, it was nothing like leather or NAO. The color and looks were very similar to Yamamoto or Nippon (just a shade lighter grey than Nippon). The dust was also like carbon (black and could not be shaken off, had to be washed off).
When will people stop making 'steel-mixed' brake pads the target of their prejudices? All branded brake pads have steel. Even Suzuki genuines ones which are supplied by NBK have steel (not more than 10%). And semi-metallic are called semi-metallic because they have 30-60% steel fibre. Since around 50% is steel (metal) that is why they are called semi-metallic. As per my to-date experience, only the local unbranded variety of white or grey leather fixed (sometimes even riveted!) to used backplates lack steel.