TLDR: The greatest FPS game of all time and worth every penny of your money. (Go cry about it BO2 fanboys)
In Depth: Pros:
Conclusion: Just buy it, you'll love it.
In Depth: Pros:
- Levolutions, amazing events that change the map in an instant
- Great dynamic gameplay with awesome flow
- Some of the best weapon selection and modding in FPS history
- Consistent and kind player base (you'll always have servers)
- Good graphics for the time, still holds up well
- DLCs are reasonably priced and worth it
- Weapon balancing is solid
- No SBMM, so there's less sweaty players
- Campaign can be tedious and slightly boring in certain places
- Kills aren't as satisfying as BF1 (I know, big nitpick)
Conclusion: Just buy it, you'll love it.