What model Wizard, decock or saftey is it blue or stainless?
If it's a stainless decock, I'd say jump on it as those are getting hard to find. But for anything else, I'd let it pass. I bought my stainless saftey model for $325.00 (with four 15 round mags) and I think I paid what it's worth. That being said...
I really like my P89...the gun is built like a cinder block, no frills all function. And it's tough enough that if you runt out of ammo (The P89 has ate anything I've put through it) and the BG is still coming at you, you can beat the snot out of him with it.
The factory grips were the only thing I didn't like, I thought they were slippery, so I put a set of Houges on it, and that cleared that up. It's heavy enough that it tames the stoutest of 9mm loads.
EDIT:
I just went to Gun Broker, and it seems that they are asking between $375 and $400 for stainless models, I don't know if they're getting that much, but that's what they're asking.