I owned one long ago.
That's a good price because they are collector items pretty much. It would be worth getting to hang onto, or if you're into collecting HKs. The price alone is low for that gun.
As a using gun, you can get alot better. IMO they suck in just about every category you can think of except value. The trigger is DAO, and weighs a ton. The gun is straight blowback, and uses extra deep rifling grooves to bleed off gas pressure, so MV is lower on the VP-70Z than other 9mms. There's only four moving parts, so they're simple as all get out and a brick would probably jam more, but carrying it would be about as easy as a brick. Euro heel mag release that's easy to bump accidentally and have the mag disconnect.
It represents several unique inovations. It used a polymer frame WAY before anyone, including Glock,did so. The way they did the blowback/gas pressure thing was interesting. The mags are a bitch to load, but they're 18 rounds and made tough. The front sight system I thought was way cool, and eliminates any problems with different backgrounds etc. I'm suprised no one has used it since.
To be fair, it's just a civie version of a Machine Pistol that could do full-auto if you attatched a shoulder stock. The VP-70M would be pretty trick.
The VP-70Z is worth it at that price, but mainly as a collector item.