One of my top 5 games to date the weapon upgrades constantly give you something to work towards, and it's just plain fun
One of the best features of the single-player campaign is the inclusion of weapon experience and upgrades that accumulate over time. Each weapon has three tiers of upgrades for it, this includes all other weapons you can pick up in the game, so that rocket launcher you found? Kill 8 Nazis w/ it and you'll gain a level. These upgrades are both practical and cosmetic, a foregrip you unlock for your Thompson SMG will improve accuracy as well as appear on your weapon. My favorite weapon by far is the Springfield sniper rifle, the upgrade tiers for this gun are Faster rate of fire, (a Stripper clip) gives you a faster reload, and finally an attached grenade launcher gives your sniper some extra oomph. (Throwing grenades upgrade just like guns do!)
My favorite thing in this game is sniping, when you headshot a helmeted enemy, you hear a little ringing sound followed shortly by your enemy slumping to the ground. I've had no problems with the hit detection or the AI, the Allied AI is pretty irritating but doesn't really take away from the whole experience.
The controls are different from the COD games, and if you're just coming off of COD 3 then you'll take a little while to adjust, but once you do you'll be very satisfied by the way things respond.Overall if you like WWII era shooters you're collection will not be complete without this gem.