The famed prerequisite to Team Fortress 2 is all it's cracked up to be.
First off, this game set the standard for what every class-based shooter should be. From the fast-running scout to the hefty Heavy Weapons Guy, this game introduces most-needed diversity in what any game should have to keep it running, and to keep players playing. Sometimes, however, it just doesn't seem like the classes are doing what they should. On maps like 2fort (CTF) or Dustbowl (TC), the Medics are the ones that are the guys pushing the flag by using their frag and concussion grenades to propel themselves towards the capture point, rendering the Scout useless and completely diverts the MEDIC'S role away from what it seems.
The game play of this game will keep you sitting at your desk for hours on hours. The on-going struggle to carry a piece of cloth on a pole to an enemy base will be as if you're running with a piece of pie dangling in front of you -- Long and annoying at first, but rewarding in the end. The stalemates of the grenade tosses at the beginning of matches can be aggravating, but you'll feel like a secret agent slipping through as a spy.
Overall, this game is absolutely marvelous, and will live on forever. This game is worth the five bucks, it's tons of fun, and it will keep you entertained for years to come.