What a lovely 5 MHz sine wave. Not sure why its coming from my crappy breadboard power supply, but hey, now I know I need more filtering. Maybe a lot more. That wave is about 0.2 V peak to peak, which probably adds up to a lot of noise coming through the OP Amps. A 10uF cap on the power rails quites it down (oddly, when I power on, its still there, but slowly fades off after about a few seconds). Also I replace the single Amp with the 10R variant of the part (not the U variant I thought it was). Except the outputs are saturated to the Amps 5v max. I'll have to probe all the points when I get a chance to see if I messed up the Amps, or if I just need to adjust the resistor values.