I finally got my gimbal adjusted and set up and attached to my FW550. For my first test flight with the gimbal attached, I switched out the 8" blades with the 10" blades. The flight went well, except I could see that the gimbal was getting wobbly as a result of a screw coming out (probably forgot to tighten them). Anyway, I took the gimbal off and flew my remaining minutes without it. The copter was very hard to fly as the altitude was erratic even in GPS mode. I am just wondering if this is a result of the reduced weight. With gimbal weight is 5.2 pounds and without it is about 4 pounds.