[Patriot86]

This has been done to death but it boils down to:

Piston Guns:
Pros:
"Some" reliability improvements (arguable point)
Easier to clean
More suppressor friendly

Cons:
Heavier(though some high end models now weigh about as much as a DI gun)
Less Accurate(again, arguable point)
More expensive(some low end models now cost as much as a "mid range" AR)
Parts availability

DI Guns:
Pros:
Lighter
Cheaper(in general)
High level of parts availability
"More" accurate(arguable)

Cons:
More difficult to clean
"Less" reliable(again, very arguable)


I have both DI and Piston guns, this is my opinion let me start off by saying.
If I am going to buy an AR, it is going to be DI period. Parts are almost universally interchangable, parts are also very available. I like the balance of a DI AR-15 more than a Piston AR-15. A DI AR-15 I feel like I can balance it on one finger.

I like Piston guns, I really do. I also own a SIG-556 rifle which for those not in the know, is a civie version of what is often called "The Swiss AK-47".
If I am going to buy a Piston gun its going to be a "from the ground up" Piston design like the SIG-556, H&K 416 or SCAR 16/17.
I love my SIG-556 but it is front heavy like most Piston designs. Its super easy to clean but the sucker is heavy. I don't know that I would want to be lugging it around all day every day.

For what its worth with about 2000 rounds through each gun I have not had a single failure of any type period. One day I might play a game of sandbox with both and see what happens but call me crazy I don't like dropping my rifles in the sand for the heck of it.