Neither is perfect, BUT ESPN 2K series is far more of a SIM than Madden or NCAA. Madden and NCAA seem to much like an arcade game.
I am holding out hope that Madden has stolen some of the SIM elements of the 2K series since they bought them out of the competition. Anyway you look at it, I already bought NCAA, like it, but it frustrates me. Pre-ordered Madden, so I am giving my $$ to EA although I think the 2K series is far superior w/ the NFL product. Just my 2 cents.
"The only thing for evil to triumph is for good men to do nothing." - Edmund Burke