I think it is neat, but I believe the way it operates simply gives the illusion of being "safer". (That is of course if you feel that hammer down carry is safer)
This is just my observation of the system, I do not own one, yet.
After the gun is cocked, when you push the hammer forward, there is a little spring tension. This tension is released when you take the safety off and the hammer springs back to the rearward position, ready for firing. The whole time the hammer is forward (on safe) the hammer is actually under slight tension to go rearward and strong tension to go forward. So, while the system is neat, I don't really see a benefit, except maybe for the no snag issue mentioned above. Plus, it seems like more small parts to go wrong at a bad time. Maybe not though, I'm not bashing it, I may still buy one someday cause it's neat
Someone posted in another thread about why he/she purchased this gun/system. He/she preferred the Hi Power to any other pistol, but was not allowed by his/her superiors to carry a "cocked and locked" pistol. This pistol fit his/her needs perfectly. A nice SA trigger pull, while not appearing to be "cocked and locked" in the holster. (Although I think if his/her superiors examined the gun closely they still wouldn't allow it to be carried since the hammer is under forward tension)
I wonder why no one has expanded on the HK P9 system. I think a double action trigger pull with a frame mounted thumb cocker would be a great system. Or a SA trigger with the same thumb cocker would also be good.