i started out on the hardest setting. this game takes a long time to play one level. the game throws alot of soldiers at you. you have a few tactical ways of dealing with them, but once you use your main weapon, half the map enemies are announced to your presence.
The enemies just keep coming. the AI isn't smart at all. it knows when your reloading or moving, so that is when they usually come at you. you could hide in a corner with a stack of bodies you just fragged and they still creep around corners like nobody is there. it's kinda dumb.
i was expecting less enemies and more skilled far distance shooting targets. i think the challenge of the game seems about right when shooting. The wind factor and bullet drops. the scenery is nice. only played half the game but it seems repetitive so far. it's not a bad game if you like challenging shooting.
it might be better to start with custom setting though if you want realistic mode. once you start the game on a specific difficulty, you can't change it back. hard mode throws alot of guys and uses alot of your time.