fortunately, i use Carl Zeiss/Leitz lenses more than Canon lenses on my eos 5d2 i have ony the Canon 100/2.I don't have 135L but in general I don't like this focal.for me my APO-Telyt-R 180/3.4 is definitely better than all other Canon lenses (for example: all 70-200 and 200/2.8)and about my Planar 1.4/50 Contax...this is a lens in all effects !!!in photography are more importants the colours and sharpness instead of flash AF of this 1dx..but some Canon lenses have mummy colours.....it is simply: a ferrari (1dx) with cheap pneumatic (canon lenses)the 135L and 200 f/2 maybe are very good...but with wide-angle, Canon is behind Zeiss/Leica...the elmarit-r 28mm rom or Distagon 28mm...the elmarit-r 19mm rom..or Distagon 1.4/35mm or the new Distagon 21mm ... you will live in another world !!!