To me, there is nothing better than a mil-sim game. Viking, Scarcrow, Meat, Ponch, you guys hit it! No other way to explain it. Nothing beats being out in the field all day/night on a single load of ammo, getting eaten by bugs, burned by the heat, soaked by the rain and eating sand covered green candies for two days. That's what I thought airsoft is all about? I find there is more of a challenge carrying a restrictive load-out, knowing I have to be strategic and I have to rely on team mates to get the job done.
However, as being one of the organizers at the LZ here in Ottawa, I don't have the time and energy to run all out mil-sim games every two weeks. I try and do one a month, like Op Razor Cut 2 and Op Red Flag next month. So for every game day, I try and do a small senario, if it lasts all day, cool. If not, we do some smaller senario/skirmish style games later in the day. Although our smaller games still have an objective of somesort and we ask players to still follow, "mil-sim rules" like realistic loadouts, etc... So I think there is a place for both styles.
As far as knowing which one is a mil-sim. I think the idea of calling it an "operation" or labelling it as a mil-sim style game is the easiest.
Just my .02
Either you are the weapon and your gun is the tool, or your gun is the weapon and you are the tool.