Most important question./..What machine you got?
Rotovac 360i and RX-20... although they will "work" with a standard portable, they really only come into their own on a high performance system.. the rotovac probably fine with a top notch machine like airflex/alltec/scorpion/jaguar but the RX definitely a truckmount tool. (OK someone will pipe up and say they use one with a porty
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Why do you want a wonderwand as opposed to a "normal" wand?
I've never used one, but lots of guys on here have so they can best advise whether it would suit your setup