Interesting point Kanik. However, does the Zee really come with resin pads with no fins?
Jensonusa sells the retail version for $129. And in its description it says.
•Radiation fin pad with new metallic compound to improve control and consistency
Shimano M640 Zee Disc Brake > Components > Brakes > Disc Brakes | Jenson USA Online Bike Shop
Maybe the blueskycycling non-retail version come without the pads? I know jenson usa won't price match blueskycycling because of bluesky selling non-retail versions.
I bought from Jenson USA, but I was upgrading from Shimano BR-M446 calipers and I used the same adapters I had on those. Each set came with new mounting screws, but I used the same ones I had on before also. On the rear there was a longer screw where I had to use the one that was on there previously. Jenson's also come with a spare parts to shorten the line(which I did easily).I think they come bundled with a metallic compound pad with a finned backing plate.
For $115 BlueSkyCycling is including the adapter bracket and mounting hardware in the bundle.
It looks like JensonUSA is charging $130 and is not including the adapter. They want $10-$23 each for those in Shimano brand. Not sure about the hardware.