For online experience check out this channel showing gameplay on ATAG server
http://www.youtube.com/user/Semashko27/videos It is better to see for yourself than listen to others ))
Offline experience is limited by not working radio-commands and AI mistakes in some situations (like crash on landing). If you do not care about friendly AI crashing sometimes and not following your orders there are many great user-created campaigns available (see link #1 in my sig).