For my board, I went the C4 route instead. Yes my C4 kicked off every other filter and octaver off my board. I've had numerous OC-2's, MXR BOD and BEF's on my board. I also have an EQ2 on my board that has a dedicated expression pedal attached to it. As well as using it as my EQ, it's also serves as a Wah, volume swell and foot controlled low pass filter (think Xerograph) depending on which of the easy to access 8 pre-sets I select. So while my C4 does most of my filter and octave (and synth) duties, some of the filter swells are carried by my EQ2.
I sometimes hanker for a Spectrum, but I'm not sure I actually need one! Maybe I'm just being seduced by the oh so funky purple graphics! Have you seen it with after market gold knobs?