for me, both cameras require some special handling. the dp1 in the post-processing. it gives you amazing opportunities.
the 5d, on the other hand, needs physical modification. in my camera madness i bought two, one with a shaved mirror so i can use the half dozen leica r lenses that impoverished me the winter before last. unfortunately, even with confirmation adapters i don't seem really good at manual focusing. the results, though, of alternate lenses changes the 5d into a different beast.
the same with the modified ir 5d. there probably isn't a better camera for it. finally got out and shot some with it last nite. takes some learning to know how much ir light present and how much isn't. however, in nature you can do some very ghostly things. i'll post a pic or two later.
i did spend the afternoon shooting with the dp1 around the tower, to see what i could find. here's one from the garbage!
wayne
www.pbase.com/wwp