Great multiplayer game with a mature community. Servers can support up to 100 players. Great historical accuracy. The game has been updated to version 4.11 so you will need to find the patch for it. To play multiplayer you will need to find and install an application called Hyperlobby. It's a shame it doesn't support multiplayer better, but with hyperlobby it works fine.
Steep learning curve for inexperienced pilots in simulators. General flight, taking off and landing, won't be easy at first let alone dogfighting and the associated tactics required. Taking off, killing an enemy plane and returning back is no easy task but very rewarding when acheived. Carrier landings are one of my favorite things in the game. Multiplayer spans from 1938 to 1946 with just about every scenario imaginable.

This game is awesome