I use the P-90 coils of my P-Rails more than any other setting. I know I've talked about the EMI noise in my house, and it certainly effects the P-rails, in both single coil modes, when only one pup is selected. (They're rw/rp to each other, so using both at the same time retains the noise cancelling.) I know I've mentioned it before, but using an EHX Hum-Debugger pedal totally eliminates the problem.