I'm writing this as someone who'd enjoy this at its prime on the Xbox.
This game had a lot of desirable elements that hadn't been seen in a lot of other shooters at the time. Yet, it still felt like a condensed version of TF2 prior to the customization. But that made it interesting. The classes by name were there, but a lot of the elements mixed together in a clunky and sometimes enjoyable game.
Like the medic aspect, it could be paired with a spy-like ability and a scout-like speed. All good on there own, all pretty hard to work with when melded together.
Would I recommend this game? Hella. If only on sale and under $5. The game has a linear campaign that repeats in a multiplayer format, which means that multiplayer to this game was almost a requirement. Within a month of buying this game, the active players number was almost gone already, and it was a bot vs bot game, which was just a merciless frustration. Buy this game and bring friends, a lot of em'. Honestly, if this game were just introduced again on a different face, it'd probably do well. It's an experience, the guns, the characters, even the movement style. But the lack of players and clunky class unity, (among other things) rightfully brought it a quick demise. I'd love to see this go F2P, because it'd pull in a lot of players and revive the servers for a short while. It has a lot of good in it, but not enough interest to inspire a renovation worthy enough of bringing it back.
Buy it cheap, play with friends. Avoid bots.