That's an interesting question. Like Hulyss, I find myself using the DP3M more often than the DP2M, due to the focal length. I think the cameras are certainly equals in terms of level of quality in output. I do think that there are subtle differences in rendering, but I find them hard to describe.
That's probably not very useful, but the short answer is that if you like the DP2M, and you'd like to have a 75mm camera, then it's quite probably that you'll also like the DP3M.