AI War is an excellent game and the AI does some surprisingly smart things sometimes (not to mention that you can have tens of thousands of units in a game).

But AI War is also a very different gameplay experience to most other RTS games, so while its a good game in its own right and does have good AI, it may leave you disappointed if you're looking for a more traditional experience.

Not to mention that its an insanely hard game but I guess that's the price you pay for "good" AI!