I've got one behind my hip right now, and it is there for most of my waking hours (at least the ones where I'm not in the pool.) As mentioned, they are heavy for the size. I don't even notice the weight now, but it's worth noting.
For me, it is the most instinctive, pointable gun I own. I actually get into some bad habits with it because I can look at the target and not the front sight and still hit what I'm aiming at.
For the cons:
Other than the weight, the guns get hot, sometimes uncomfortably so, if you shoot a lot. This is not a problem for concealed carry but if you are taking them to the range it is good to have a few other guns to shoot while the P7 cools off. They also require a little more care and cleaning than a lot of other guns on the market. After a lot of shooting you can feel the slide start to move sluggishly, and this is a sign that the gun needs to be cleaned. Again not an issue for CC, but something to know.
The finish does not hold up well to holster wear, which will be the main differences in the Grading system. I always encourage people to get a grade C if they plan on carrying the gun (and can find one, the grade Cs went cheap and fast), because a grade A will likely look like a grade C after a couple years in a holster. Even with the poor finish, mine has no problems with rust, but some people report such.
If they work for you, great, but there are some of us who have tried them and decided against them.
This is true. A lot of people that shoot mine love it. They love the trigger, squeeze cocker, thinness, etc. Some people hate them though. They certainly aren't for everyone, but if you get one and you don't like it you probably won't lose more than about $50 upon selling it.