You will be running just as much as the rest of your team.
I have used both the CA and Echo1 extensively in airball and have found both to perform well. Both need some lightening up but the echo 1 is a tad lighter to begin with. Get the long barrel version, you can always put on a para flash hider. The para stock is heavy.
Both can run away on you after a while because the bump switches that run the motors tend to get hot and either arc together or melt the housing and cease to turn on.
CA box mags are nice but not big enough, MAG mags need some modifications so that they don't jam, and the stock CA big mag tends to self destruct if you bang it around too much.
The echo 1 saws are not that expensive. I would not pay more than $500 for any airsoft gun, except a TH m240 or a minigun. There are plenty of used ones on the market that are in great working order.