The Sigma approach is finally getting the recognition due...

check out diglloyd,  luminous landscape or just search the web. As far as IQ is concerned these guys are amazed at the dp-m series. When people that are used to shooting MF, digibacks, high end dslr etc. with the best glass ( Leica, Zeiss etc. )  are impressed with its IQ that is getting recognition. It is what most that shoot  sigma cameras have always seen and known. All this in a 1k package, one top quality lens to match the dp series quality from Leica, Ziess, canon L or Nikon gold will set you back more than the whole dp-m and will be bigger and weigh much more  just my 02