As the sequences get more complex, they also get longer, so the need for capacity goes up. I am currently flying a 2M Vanquish using 4400 mah packs. I am still getting used to the plane, but in general I will use about 2500 mah for the Intermediate sequence. I normally set the timer for 7 minutes which allows me a few additional passes/maneuvers. On a really windy day, I have seen consumption go up to 2900 - 3000mah. For the sportsman sequence, I would imagine that the consumption would be closer to 2000 mah.

Good luck,

Teo