Tough one. I usually get hooked on one brand of developing chemistry at a time. For the last 2-3 years it has been Tetenal, for a number of reasons - one of the most important is availability.
I have used Photocolor and I don't remember any *great* difference between Tetenal and Photocolor.
There IS a great difference between papers - Ilfocolor, Fuji, Agfa Signum, Kodak ... all require significantly different filtration. I had been using Ilfocolor (present and future status in doubt) for its consistency: *no* difference when using different sizes, very little lot-to-lot variability. I can't say the same for either Kodak or Agfa. I've just started with Fuji Crystal Archive, so I can't really comment on it yet.
2-3 cc Difference? I've seen about that much between frames on the same roll of film.