I bought one directly from HK back in the early 80's when they were $200 with four mags. Even at that deal, I gladly sold it and haven't regretted it (at least no where near as much as selling those HK94's at $550).
It's very interesting from a design and engineering point of view. The pistol is straight blowback. That's why there's such a huge slide on the damn thing. To keep the pressure down, the rifling was cut extra deep and actually is designed to allow gas to blow by the bullet as it travels down the bore. MV from the VP70Z is lower than other 9mms of the same barrel length because of this.
The heel mag release wasn't the best design either. It was very exposed, and I managed to bump it a couple times while shooting and had the mag drop out of the gun.
The sights are really fascinating! The rear is normal, but the front is actually a slanted block of steel. There's a channel milled in the block, and the two sidewalls are left in the white and polished. The channel appears to be a front sight post, due to the shadow, when you look at it through the rear sight. Also as you look at it the walls on each side take up the rest of the sight picture. So you actually see the exact same sight, with the same contrast, and same look and everything, no matter what the background is. You can't see the background around the front sight blade, because it doesn't have one. Just a block of metal with a channel in it. It's goofy sounding, but it actually worked quite well, and I found it a very interesting way to adress the way to sight a handgun. It didn't matter what you aimed at, all you saw was the shiney, white metal side walls and the shadow of the channel between them, and it was a VERY functional front sight. I'm suprised no one has tried a variation of it.
Anyway, the safety is right where the mag release for a M1911A1 is, so there's some training issues to be considered if you're thinking of carrying it or anything.
There's only like four moving parts to the whole thing, and I really can't see anything stopping the gun from working. It was quite simple. The trigger blew like...well it was really bad. This was one of the first DAOs, so there's some forgiveness for that, and the thing was designed more for use with a shoulder stock anyway. The stock had the burst control on it, and to get it to fire bursts, the stock had to be installed on the VP-70M. Otherwise it was semi-only, without the stock installed. The civillian VP70Z had no fittings for the stock.
For use, I wouldn't recommend one. A VP-70M with a stock, on the other hand might be kinda cool. As a collector piece, the price has steadily risen on the VP-70Z. I think it's a good buy for the collector, or to round out a collection, but not really for someone looking to use it for any serious use. There are simply better guns out there for the same kinda money.
Ross