Stock DD on the Gold Racer. Only have the one coil on that machine and for what I use it for it is fine. I had a concentric for a Gold Racer but it was knock sensitive and separation was terrible. Unlike other digital machines the Gold Racer doesn't lock onto a target so it takes some getting used to. Targets next to each other will have their id's show on lead edge of swing. With that in mind you can approach signals from different directions and determine if there is more than one target in the spot. Takes bit more work hunting in high trash areas but still effective.

Machine has been able to hit a dime at 10" which is plenty around here.