Generally Stainless Steel, technically SUS303, is not proper material for an electronic gadget cabinet especially portable device.
 
Because Stainless Steel has much stronger hardness and tensile strength than Aluminum (Duralumin is also kind of Aluminum) which means it has very BAD machinability and it makes extreme hard for manufacturing process. So normally Stainless Steel is used for tools and mechanical parts.
 
Nevertheless its high manufacturing cost, but the build quality and feeling of its raw material gives exactly what we desired for AK240 special edition. For this same reason, your Rolex watch and its strap are made of Stainless Steel.
 
And what about the different sound? Any sonic change with Stainless Steel body?
The answer is “Yes”. Because GND is one of factors which affects sonic differences in HiFi.
 
The AK240 has limited GND areas with its anodized Duralumin body but this pure Stainless Steel body using its whole surface as GND points and it brings sonic changes from AK240. So without any H/W and F/W changes, we can achieve more clear and focused sound like you never experienced from the AK240.
 
Also its new French leather case and Carbon fiber with glass back plate adds to its value as a special edition.