Couple of questions about expression pedals if anyone can help.

I'm planning on buying the EHX Worm XO (http://www.ehx.com/products/worm), and an expression pedal to go with it. I've been looking mainly at the Roland FV500, and also at the Roland EV-5 as a cheaper option.

I think the EV-5 would probably be all I need, a basic expression for The Worm. The FV500 is obviously the better pedal, but would it be worth the extra £15ish? Will the basic EV-5 be enough? Does anyone have one, is it a decent pedal? I can't find many reviews at places like Harmony Central, so I'm unsure.

The extra 15 quid isn't a big issue, but obviously I'd rather save it if the EV-5 is good enough.
Thanks for any advice.
I dunno, I'm not sure what type of pedal you have to use with it, I'd check on that first.
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