Arma Is arma fun?

It really depends on what style of gameplay you are into, the most fun I've had in ArmA is running with groups doing large coops with like 50-80 players (fighting AI). For me that's the most fun ArmA gets - I have never been into the ArmaLife stuff, so can't comment on that. This is coming from someone with over a thousand hours in Arma 3 and about the same in Arma 2.