Dominions II tramples MoM, and all other computer fantasy strategic conquest games, for my money anyway.
The many bug reports are mainly from fan enthusiasm. Getting fascinated with the many details has people noticing and wanting to be helpful when things go wrong. Except for those who expect the AI to act with human intelligence in a game of unmatched complexity for its type.
As for completing a game in a day... that depends on the settings. Maybe on a small map versus one AI. I still haven't completed any SP games except the ones where the AI wiped me out. I've been playing Doms I and II for months and still haven't seen half the stuff. I've only played as four of the major races in Doms II (eight in Doms I). I've got years to go before I've seen everything.
Fully recommended to those who can see the potential from the demo. Tip of the iceberg.
PvK