Because I've never finished it, I can't say whether or not there's any bugs or anything that make it unfinishable. My reason for never finishing it has to do with life, and not the game. Beautifully written, especially for when it was released. Great art, for when it was released. Creative magic and technology system. An amazing world to explore. If you enjoy Final Fantasy, Elder Scrolls, Neverwinter Nights, Pillars of Eternity, Divinity, and similar games, you'll probably enjoy this game. It's magic & steam punk. A bit like Shadowrun and Numenera.
This game kicked off the whole series of "Quest" games by Sierra. As others have said, the VGA version is better. The whole series gets better as one moves from start to finish, in my opinion. A real classic, that I highly recommend for people who enjoy adventure games.
QFG2 is my favorite game of all-time. QFG1 is my second favorite game of all time. It saddens me that the series actually became worse over time, with bugs (that have since been patched, I believe) and trying out new technologies that made the games look cool, but took away from them a bit, I felt. Even so, I'd put any QFG game up against most modern games. The series just rocks.
I like Mission Force Cyberstorm 2, and Mission Force Cyberstorm 1 is a better game in my opinion. I wish modern games would be as good as the old ones. The only thing I don't like about this game, is the map size. I wish the maps were bigger, but for when it was made, it's a great game.