I think the P17 is super cool and recommend it to anyone. Can't beat what you get for the $. I have two now, and may buy another.
That burr on the port thing is apparently somewhat a common issue, and probably the #1 reason for complaints and returns. Well, leakage is the #1 complaint and most who have bothered to fix it say it was a burr. I think 90% of people just return the gun so we can only guess. I checked mine first thing and it seemed ok, but I smoothed it anyway because the O-ring no doubt squishes into the hole as it passes so it might get tore up from a burr deeper in. Or just shoot it and see if it holds or not. Mine came with a #117 O-ring, which fits mine better than 116, but others say a 116 fits better. I suppose mfg variances between both the gun and O-ring will determine which works better for you. Testing for leaks is easy, just leave it pumped overnight then shoot it. There are also two O-rings on the valve, and one between the piston tube where it's crimped to the chamber assy.
You can do some improvement mods to them too, here's a link with some ideas:
http://tinyurl.com/ntzmy4t I think #1 is a trigger job, but I also disabled the auto safety, blued all the chrome parts, and smoothed/lubed everything. Be sure your piston is bottoming out in the tube so you're not missing out on any air. Mine were fine but apparently some guns come up short. Be sure the breech end of the barrel is smooth and rounded enough at the bottom so it slides over the breech O-ring w/o damage. I rounded mine a bit more just to be safe and smoothed the surface finishing with 2000 sandpaper. Then dry lubed it with tungsten disulfide before wet lubing, which I do on all moving parts of all guns and virtually everything I own. I use regular Red n Tacky grease for most everything too, but mixed with syn motor oil and dry lube to thin it out and make it better.
I haven't had a need yet for maintenance oiling, but I'll probably use a drop of syn motor oil or tranny fluid. I think oiling every 1-200 shots is excessive, but if you turn the gun upside down for a while then dry fire it it will spit out any excess. If oil is allowed to build up in there it will have obvious drawbacks.
