it's not really any harder to tune, but i haven't been too impressed w/ many d-series aftermarket cams.
i've tuned a few w/ the bisi cam and that's the one i'd lean toward or the skunk2, however i've seen one of each break. if you go non-vtec the only real option is the bisi.
the one car that broke the bisi cam actually had a better powerband after putting in the stock cam.