Things I liked: Blowback is just plain cool/fun. I can get 130 or so carefully aimed shots out of one CO2 canister. I'm not into rapid fire (as\ a resul I don't go through CO2 like crazy) and, in spite of what people say about this gun and smooth bore pistols, it's pretty darned accurate (shooting at about 15-20 feet from target). Only wavers when my concentration does. Pink's my favorite color. My father's quest for a fun BB gun took him from a Makarov with grips that slid off too easily to some other pistol whose name I can't recall that had a trigger pull that required two hands to, finally, the PPK/S. And, after letting me try his and seeing what a kick I got out of shooting it, he got one with pink grips for me. They are the same pistol, obviously, with different color grips.
Things I would have changed: Nothing, really, except for a small issue I'll mention below.
What others should know: There is one issue I've read about with this gun that I also experienced myself, and that is that after shooting it for a couple of weeks, the slide started sticking. It would cycle all the way to the rear but on the way back, it would get stuck about 1/4 inch from the front of the barrel. Fortunately, I remembered having read a comment on the pyramyd air blog (the one written by Tom Gaylord, a.k.a. BB Pelletier) that mentioned this. Several months later, someone else came along and posted about his similar experience and what he found to be the problem. For the sake of other PPK/S owners, I'm providing the link below. If Umarex could figure out what causes this--and why it doesn't happen with all of the PPK/Ss; it hasn't happened to my father's--and fix it, this gun would be perfect, IMO. Here's where I found the solution to the problem I was having with my gun: http://www.pyramydair.com/blog/2005/12/walther-cp99-compact-walthers-other.html
Things I liked: The price is great, especially if you just want to try out a scope before taking the plunge with something more expensive. Unlike people I've seen badmouth this scope elsewhere, I didn't have any trouble getting it zeroed (it stayed zeroed as well) and it wasn't already broken before I got it out of the packaging. Optics are not super clear/bright, but it's a $10 scope. It works well for what it is.
Things I would have changed: 1) The adjustment knobs, for one thing. I don't know what kind of metal they're made of, but it's rather soft and easily deformed. I took to using the widest screwdriver blade (the pry bar, actually) on my SwissTool to adjust windage and elevation because anything smaller started to mangle the slots. 2) Make it just a teensy bit sturdier. Mine broke when the gun it was mounted on fell over (not out of anyone's hands; it was leaning against a wall--inside corner, actually)--and it fell over. The scope took the worst of the impact on a brick step--has a ding in the tube--and refused to zero afterward. I contacted Crosman and was told I could sent it in, but that would cost nearly as much as the scope did. I've chosen to replace it with something else.
What others should know: As I said, I've seen some pretty bad trash talk about this scope, up to and including claims that it's made of plastic. The eyepiece is obviously made of plastic, but I can vouch for the fact that the scope tube is made of aluminum. The ding on mine went through the paint and left a gouge in the metal.