I nearly forgot about the rare "10" version or the .40S&W caliber P7(10mm).
There was no actual "10mm Auto" P7 to my knowledge. The P7M10 was a modified P7M13 that held 10 rounds of the then new .40 S&W.
I worked at Shooters World in Phoenix in the early 90s when the P7M10 came out. The first one we got, which we had for less than a day, had a "standard sized" slide. H&K made, according to some, less than 300 of these guns... personally, I think far fewer than that... and I also think we never should have received the one we did.
The owner took the gun out of inventory 2 hours after it hit the display case... and we never saw it again.
If you ever see a P7M10 "slim slide"... just buy it, and don't ask questions. Know what I mean?
The first "fat slide" P7M10 we got 2 weeks later... was a top heavy, ugly, clunky to shoot POS. H&K jumped the shark with that gun... they should have developed a dedicated recoil system for the gun instead of the stop-gap, brick they went with.
All IMO of course... but I know a whole lot of P7M10 owners, and without exception, the guns are investment safe queens.
As the P7 is history, it's all kinda moot now. I just wish they would have brought the P7M7 to market with the expensive hydro buffer... even at an early 90's price of (the H&K estimated) $1400, I think it would have done OK.