I tried it...for some reason I liked Warcraft II better. Can't really say why. Among "town-building" RTS games, I like Age of Kings best.
We got so efficient at building in that game it was scary. We were well known at the 2 college comp labs as "The Four Horsemen." Sad, I know.
However, we got burned out. Once you figured out easy counters to weird strats like "Tower Method," the game reduced down to which team could develop blood-lusted ogres first. Game over.
WCIII is different - the RTS part of the game is so complicated, it's difficult to always know what to do. It's even worse with the expansion, so all we do anymore is play hero boards on Battlenet. Some of the mods are great and make for interesting games.