Hello,

in my experience (using 4 YS 63S) the fuel consumption is about 35CC per minute on 30% Nitro (CP Heli HighPerf.) and about 30 CC per minute on 20% nitro with 12x7 APC.

On 2 of my airplanes I'm using 12 Oz tanks. Both other 2 I've got Tettra's 400 Ml (14 Oz). Taking into account a safety reserve (i don't fly untill empty...) these tanks give me approx. 8 minutes and 10 minute flights.

I'm flying on average at high throttle.

Based on your description of style of flying, my best guess is that 10 Oz should get you a safe 6-7 minutes flight, that's ok.