I have both the PSP and the P7M8, the same gun but with the more modern lever mag release that HK has adopted. The P7 has some unique features and is a great collectable IMHO. Though not small, it is pretty compact, especially considering it has a 4" barrel. The action is very safe, which is it's lever cocking mechanism's main benefit. It is cocked or uncocked very quickly, very easily.
The P7 is an easy pistol to shoot well. The trigger is light and short and the fixed barrel is am accurate platform. Reliability is another P7 attribute. I've owned one for years and have yet to have a problem.
* The slide is heavy to rack. The spring is rated at 24#. It's a "man's gun"
* The cocking lever is easy to manipulate and requires very little effort to hold. No "death grip" needed.
* Takedown is easy. Cleaning takes a little effort as there is the addition gas system to attend to. I use Slip 2000 Carbon Killer on the piston... works well after a few minutes soak.
* The grips are locked in place, so take care when removing them.
* This is one gun you WANT to read the manual on before working on it. It's different.
* The trigger area does get hot after shooting a number of mags. I have a bunch of mags and when I shoot fast, a quick 50 to 80 rounds, the gun gets too hot to comfortable handle. Many people take another gun to the range for cool down times.
* There are two types of PSP, mag release differences. Know which you have before swapping grips.
* I love the chamber.
I really enjoy my P7s. I am certified HK-oholic.
It's a great gun, easy to shoot and will put a smile on your face I believe. Enjoy it.
Good info here;
http://hkp7.com/qa.htm