My SSE had a Super Tigre .45 with an 8 oz. tank and I don't recall ever running out of fuel. Flights of 12 minutes were standard and most at 3/4+ throttle. How long did you want to fly the plane? Just thought I'd ask as you may not need to go to the 10 oz. tank. On the issue of a tank hatch-I had one on mine and probably would not do it again. It does weaken the structure. Man, I sure miss my SSE[]