I bought a LC9 about 1 month ago and shot it the first weekend I had it. I shot 100 rounds of Remington FMJ rounds through it without a hiccup. I also shot 50 rounds of old, mixed carry rounds I had accumulated through the years. All but one of them fired flawlessly. The one that didn't was an odd shaped hollowpoint that caught a little on the feed ramp. I taped the back of the slide and it chambered and fired with no further issues. I also shot around 25 rounds of 124 grain carry ammo with no problems. I found the accuracy to be very acceptable at 7 and 15 yards at an indoor range. I'm left handed and didn't have any problems with magazine releases, manual safety engaging, or slide failing to lock open when empty. I'm planning on carrying it in my front pocket with a Nemesis holster. I'm very pleased with it so far, overall.
I shot it again 1 week ago. To begin with I fired all of the 124 grain hollow points that I carry with it, in 2 magazines. Both magazines fired flawlessly. I then fired another 100 rounds of Fiocchi 124 grain hollow points without any problems at all. I've cleaned it after both firings and have not noticed any unusual wear on the guide rod or other parts.
Overall, I really like this gun. I'm carrying it in my strong side front pocket with a Nemesis holster with a spare magazine in my weak side pocket.
I picked one of these up on Friday along with a Ruger Single Ten. I shot the Single Ten on Saturday with plans to shoot the LC9 today. Due to the crappy weather, I didn't make it out today, but I am dying to put some rounds through this thing. I normally carry a J Frame, but the LCP is a little shorter and thinner. The only advantage the 642 has over the LC9 is the weight. The loaded LC9 with holster is about four ounces heavier than a loaded 642 with holster, but that's nothing in my opinion. If this thing shoots as well as you folks are saying it does, it will definately make it into my carry rotation.
Sellior & Belloit [sp?] ammo is known for having some particularly hard primers. If you absolutely have to shoot S&B ammo there are some replacement springs available from Galloway Precision, but there is a lot of other 9 mm ammo out there.
Some folks have complained about wear on the guide rod if they shoot a lot of +P ammo. For those folks Galloway Precision and Steve Bedair both make precision engineered stainless steel guide rods.