I use to play
Even had a small shop and worked on guns
I would spend almost $80 a week on paint ..... its a rush
If they play a lot I would suggest getting them a chrono its well worth the money I have been shot real close and been shoot up pretty bad but to me it looks like the guns were shooting hot when I played max fps for any field was 300 fps some were conservative and go 280 fps

Nitrogen shouldn't spike
Nitrogen and compressed air was the answer to pressure spikes you would get when you would use co2 in warm weather

If you were in a tournament and shooting with co2 its a good idea to chrono a little low incase you had a presher spike when your gun was being tested because if it test fired over the field max fps you would get disqualified from the match

This may sound crszy but after you play a while you get used to getting shoot so its not that bad ...... sometimes i miss the days when we played but i couldnt keep up with the pace anymore (i barely could back then)

Now we play airsoft its a lot chesper and no gas bottles to fill

Heres an example of how long it has been since i played ..... back then autocockers were heavy hitters and shockes had just got the new smaller body style and the freak barels were just getting popular ..... lol ...its been a while