I don’t think GPS is going to be your problem. More likely you’ll have harmonics interfering with the 2.4 signal to your receiver for control of your copter (unless you’re using UHF). You should use a notch filter for your video TX to help prevent that.I've got a 1.3 GHz skew planar wheel on my 550 with a 300mw vTx, I was wondering if there is any interference with it and the GPS antenna? or how close they can be mounted? I've used OSD's with no problems.