3DAP,
4S 3000 mah is the ticket for roughly 10 min of good 3D. Andrew said that he likes the longer flight time with minimal weight penalty. As a bonus, you get better wind penetration also (just check his SEFF video). If I were to prop down, I'd go 12x6 instead, but I just can't let go of the power and speed I get with the 13 x 6.5. I think APC also makes 13x4 which will be more suited for 3D application.
Thanks to Pete from my club for getting some more AJ Footage.[link=http://young99.net/../images/Videos/AJX%204.wmv]AJ Extra 330S 4th Video[/link]
If you squint hard enough, you can see a 1 roll circle at the 2 min mark
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