This is a great game and there was never a dull moment. Here is what I think about it:
- Graphics, sound, gameplay, plot
- Weapons can be bought but are also unlockable through radio towers
- Side missions & hunting was fun
- Good fast travel
- All the characters were memorable & interesting in some way, loved the bad guys in this game
- Skill tree builds on your character as you progress
- AI is decent (they try to search for you, flank, and/or draw you out)
- After you complete everything (outposts, radio towers, etc.), there are only a few spots on the map with bad guys remaining which makes continued adventuring not much fun.
- I noticed one skill (reloading while sprinting) that didn't function (maybe it was just my game, idk) but it didn't really bother me
Overall, single player is a great experience. I'm just now starting the multi-player to get the coop achievements. I would say the multi-player is just "alright" and is nothing special. Rent or buy it only for the singler player experience alone.