First let me start off by saying I love my HK's and own 7 but I have a buddy that called me today and and asked if I wanted to buy his USP9 SD but there is major problem with it.
He bought it new in box but it came in did not come in a case it came packed in a white cardboard box, from what I read these were LE demo guns and a few were sold to the public. He fired exactly 6rds through it and on the 7th got a squib round and fired the 8th round causing the barrel to spit at the threads. Instead of calling HK and lying telling them it split after a normal round he told them what really happened and they told him they would not warranty the barrel. So instead of taking it to a smith and having them cut it at the treads and recrown it as a standard length barrel he used a dremal to cut it in half. I checked it out and all seems fine and used a barrel from one of USP9s and it ran fine.

The deal includes
Cardboard box
5x15rd mags
3x10rd mags
Adj, night sights
Gun
No barrel
$450
I found midway has factory threaded barrels for $250 or I can order an aftermarket barrel for $250but then im into the gun for $700 with a non ser# barrel in the gun. I know when these sold new this package would be around $1K with the mags but I am unsure if its worth me puttin the money into and if I could make my money back if I had to sell it in the future.

Also does anyone know if I sent the damaged barrel back to HK if they would sell me one with a matching ser#?

I just got a new USP 9 SD (isn't even here yet) from policeguns.com (clyde armory) for 899.  Mine has less mags and no night sights but comes with the tactical case.  It could be a good deal for you if you don't mind spending the time and money to get it back to 100%.  If i'd had that offer I probably would have taken it.  Hope this helps

I'll buy it and save you the hassle.

B