I have now flown this plane seven flights, and it is a blast. My first trip to the field was a bit windy, and I didn't bring an assistant to time my flights, but I got in four flights.

It was a tad tail heavy with the 2150mAh pack, but it climbed like mad, and fought the wind pretty well. While I was recharging the 2150 pack, I stuck BOTH of my 1550mAh 3S packs in the plane and plugged them in one at a time. Obviously, the flights were pretty short, but still fun, and the plane balanced much better. After the 2150 pack recharged, I strapped two AA batteries to it for added weight and took it back up. It was really windy by then, but very fun to fly.

When I went home, I soldered up a Y harness so I could run the two 1550 mAh packs in parallel. I also added spacers to move the motor forward by 1/4".

I went back to the field again yesterday, with no wind, and with my trusty 10 year old assistant armed with a stopwatch.

I flew the 2150mAh pack, with a few extended vertical climbs, for just under 6 minutes.

I flew again with the two 1550mAh packs in parallel. Got the same perfomance, and had a flight of a few seconds short of 9 minutes.

After about a 30 minute charge on the 2150 pack, at 3 amps, I took it up for another six minute flight. It just gets more fun every flight.

In summary, we were at the field for just under an hour, I got in two six minute flights and one 9 minute flight. I am trying to decide if I should buy a couple more 2150 packs for $20 each, or four more 1550 packs for $15 each. I looked at ~3500mAh packs, but they are closer to $50 minimum. (These prices are all Zippy packs from Hobby City.)