[kalimus]

Originally Posted by Dangeruss

If I wanted to pay that much I would've probably moved up to a KAC.

I picked mine up for $2400. They aren't cheap, but I really wanted gas piston, and got hooked after shooting my friend's P415. It's very solid, and I really like the NP3 coating. It was designed to run completely dry if necessary.

I haven't even had a chance to shoot the .308 yet, but my P415 is great. I took it straight out of the box and shot 200 rounds through it without a hitch.

My AR is a gas impingement. There are a advantages and disadvantages to each system. I would like a piston rifle as well, because I think in a SHTF situation, the piston rifle will be better suited as it doesn't require the same level of cleaning (all that gas doesn't get into the upper). On the other hand, it is more parts to possibly fail, they are generally more expensive, and the hit of the piston can cause the bolt assembly to "see-saw".

That being said, I've never read anythign about noticable increased wear on a piston system, or it's piston being fragile. And as far as DI goes... the Filthy 14 is proof of how much buildup it can take without cleaning, as long as it's lubed. A piece from that article:

We received the carbine in late 2008 and put #14 into service shortly thereafter.
At Brady, Texas, in March 2009, it suffered a malfunction, which was reduced with Immediate Action. The bolt was wiped down at 6,450 rounds.
At Prairie du Chien, Wisconsin, in May 2009, it had several failures to extract, and the extractor spring was replaced at 13,010 rounds. This is far beyond the normal extractor spring life under these conditions.
At Wamego, Kansas, in June 2009, two bolt lugs broke at 16,400 rounds. We replaced the BCG. Considering the firing schedule, this is within normal parameters.
At Columbus, Ohio, in November 2009, we had several failures to extract at 24,450 rounds. The shooter gave it a field cleaning and replaced the extractor and extractor spring.
At 28,905 rounds, we finally cleaned Filthy 14. As part of our year-end maintenance schedule, we inspect and replace parts as necessary. Filthy 14 looked like the inside of the crankcase of Uncle Ed’s ’49 Packard. It was disgusting to look at and contaminated everything near it, somewhat like the toner cartridges for old printers.
I plopped it into a parts washer filled with Slip 725 parts cleaner, and 20 minutes later it was clean. Mostly clean, anyway.
We have never used a bore brush in the barrel of this gun. We did run a patch down the barrel twice, but that was all. At 50 yards it still shoots two-inch groups, and we understand that it might not at 100 yards and beyond, but we are happy with the fact that, even at 50 yards, the gun is capable of tighter groups than most of the people running it.
We have never used a chamber brush in this gun either. We were often told that this was an absolute must.
Sure…
At the last class in Casa Grande, Arizona, at approximately 30,000 rounds, we had several failures to extract. We replaced the extractor spring and wiped down the BCG.

That's pretty impressive for any gun. I likely will never fire 30,000 rounds through my rifle. I guess there really isn't much of anything that says "DI or Pison is better than another". I HAVE heard they feel a little different to shoot as far as recoil is concerned, but I haven't had the opportunity to see for myself.