This game 'should' be the best of all time, but settles for 'decent.
As far as realism goes, you most likely wont find much better. Firing a weapon in this game just has alot more of a natural feel to it, and you really will take advantage of every bit of cover you can get or you'll die. Actually you'll probably still die alot. Even really good players die in this game frequently because it really is challenging, and not like almost every other fps out there. It will take more then just muscle memory to win at this game, and thats more then i can say for almost the whole fps genre.
But i feel its my duty to help steer you away toward some infuriating problems this game can provide.
1. I dont care what kind of pc you have, turn the graphics all the way down. My hit rate doubled when i did so, and my machine should eat this game for breakfast.
2. I personally never play tank levels. Certain maps that include one or two are ok, but tanks in this game are the worst example i can think of. The smallest/crappiest rl tanks have the most armor, do way more damage, are physically smaller etc. Hit locations and shells bouncing are from some cartoon fantasy land (ive bounced more then 40 shells off his lower tracks and soft spots), and most people that currently play tanks have learned how to shoot others before their even in drawing distance. Tanks are a terrible incarnation in this game, and the worst tank representation i can think of. Many people think this is the best part of the game, but as for me i cant stand even a few minutes of tank warfare in this game. Its just ridiculous.
Avoiding the above increased my enjoyment immensely. Its still a cheap fps, and you can see this evident in the normal hit location system as well. Ive had many times where the only thing exposed is my face or head, and somehow i get shot in the toe or knee.
Hacks are very common unfortunately, and you will die when no one should have any idea where you are, but its still worth checking out, just be careful with open spaces, and expect some folks to just always know where you are no matter what.
Lag is the usual crap you can expect from any fps, so expect a few times of totally missing that guy you couldnt possibly have done so. The strange thing about this game is i believe you will desynch from servers from time to time but only partially. Everything will seem fine and dandy, then all of a sudden you CANNOT make any kills no matter what you do for sometimes entire games at once. This is probably my biggest or second biggest complaint about the whole game, it really can get on your nerves when your 30mins into a game with no kills but dozens of failed opportunities for no real reason. This game can act very broken sometimes no matter the range or weapons your using.
The maps could be smoothed, you tend to catch on very small objects which can spell certain death.
Either way, the game overall is probably still the best realistic shooter available (that wasnt hard!! lol) and its worth picking up. I think the ballistics beat even games like the arma series, and theres few technical problems (i had to almost become an engineer to get arma to work and function especially with all the abstract mods). Theres no single player which is very strange and should cut the score down, but the gameplay itself makes up for it. Its just too bad the community is thinning, but the next game is in development.
Overall the score would be higher, but for the afore mentioned problems, but overall its still one of the best shooters of all time. Just remember to lead and raise the target, and keep your head down!
The other expansions imo suck. The only weapons they provide are mg's and bolt action guns, and im not very good with either, and many of the maps are basically open fields with a cratter or two on them to hide in. Perhaps thats why no one plays them.