I would suggest instead of bigger get more. WAY back i before I could get nitro anywhere close I needed to use co2. I would use a couple of shorter tanks. a 9 and 12 would last as long as needed and then some.
__________________
Less Balls More Nuts.
PUMP PAINTER
I had a 9 and 12 but then i just got 2 20oz's they lasted for about 800 shots on my spyder compact and 1000 or more on my impy nothing i have nitro though.
__________________
SELLING
~2003 Impulse with
Eclipse Magnetic Blade Trigger
Pychoballistics Bullet Drop Forward
Low Rise
Extreme Rage Timer Grips
Smart Parts Voodoo bolt