Are you using the DYS XM20A ESCs, and if so, have you updated the firmware? From what I was reading over here:http://www.rcgroups.com/forums/showthread.php?t=2545555 it can make a significant improvement.
Cheers!
LitterBug
<edit>
I see from the link you are using the SN20A not the XM20A.
</edit>
i guess version 2 is the updated software version.. i almost went with these for my martian build but went with little bees pros instead. i am using the xm 10 a with the dys 1104 tho as i just bought the motor.esc/prop kit for 80.00 or so.. in hind sight i wish i would of went with 1304 motors.
chris.