First time playing airsoft, came in with a friend of mine and rocked hard from 4-8pm for $50 (included rental gun/mask, admission and 4000 BBs)... Tons of fun - though you can really rack up the battle scars/welts after a couple of games.
It does get hot in there running around with adrenaline pumping but it's bearable and based on how hard you go.. The variety of game types and rules was great as we frequently switched it up: Team deathmatch, medic, briefcase search and destroy...and at night we played in the dark: prison break, zombies..
Would suggest eating before/after as the food options are candy/soda/pizza/pretzels...