Recommending this game is a no-brainer. If you are even marginally into shooters with a nag for realism Arma 3 is inevitable. The game won't let you in easily; it has a steep learning curve, and starting out can be quite frustrating. Also, you are less likely to find good public servers; it hardly is hop-on and play like CoD or Battlefield.

The best way to experience it is in a clan or community group. Groups range from run-and-gun type gameplay up to strictly milsim stuff, so there should be something for everybody.

Bottom line, go get it. It's unique, in every aspect.