If and when I get a AR-10 platform for target shooting, I am getting DI. I only shoot 88 rounds in a day in an Across the Course Match. The DI system has less moving parts and is better for target shooting.
However, one of the Army Reserve shooters I shoot with, a gentleman who has been on a number of deployments, while he target shoots with a DI, his home defense rifle is a gas piston. He says it runs cleaner and cooler.
If I'm not shooting, I'm reloading.