First off, let me state that I'm just getting into airsofting after moving to central Flordia, after playing milsim/scenario paintball for several years up in southern Georgia. I've done a couple games with rental gear now, and am just getting to the point where I'm buying my own basr: the gas-operated G&G L96 or the AGM L96 spring-operated rifle. (I live in Florida, so the humidity is something to take into account.) Prior to getting into paintball and airsoft, I was in the USMC infantry.
In paintball, I pretty exclusively played the role of infiltrator, scout and flanker. While my friends shot thousands and thousands of rounds with their fully automatic markers, I had a single-shot A5 that never failed to fire. I stumbled on airsoft by accident - my girlfriend's son got a couple cheap pistols for his birthday and I was like... hmmm. These are pretty cool. I wonder if there are sniper rifles in airsoft... looking forward to relearning all my fieldcraft with a little bit better range and a lot more accuracy.
Best game moment (though this was a paintball game, this is more about being a sniper than what size balls I was using): During the night portion of a 24-hour milsim game (which my side was losing badly), I decided to sneak through enemy lines to relieve some frustration by going on the stalk. After setting up a hasty ambush of one of their squads (not wiping it out - I took out two of them and retreated before I was compromised) I managed to infiltrate the enemy command post and take out everyone inside.
While we still lost the game, it was a huge morale boost to our side. The OpFor team (it was about 100 on 100, but they had several tight-knit, well-organized squads, while we did not) had beaten us at pretty much every mission, and almost every objective. That game still felt like a win, no matter what the points said.