Took the new Fisher 15" coil to my Union Campsite today. I think my arm is going to fall off! The coil does remarkably well on small and shallow targets for being a 15" coil. It did provide a more solid target ID on 3 ringers 10+ inches (this is really better than it sounds, in the river rock soil of this site the DFX would only reach about 4.5 inches, the Explorer SE would go 6 inches and the F75 with the stock coil would max about 10 inches but it would be REALLY iffy after 8 inches. I did go 13 inches on a 3 ringer with a pretty good signal (jumped 45-88 but was in the upper 70's and low 80's mostly) Although with the stock coil the 3 ringer would ring in about 56-64 and a WIlliams Cleaner 42-48 the 15" coil would ring them in higher. Down fall? Heavy. Not just a little heavier than the 11", much heavier. After 2 hours I was down right tired. Not sure if the gain in depth is enough to swing it for any amount of time. I was using it on a standard F75 and not the LTD. I am used to swinging an Explorer SE with an SEF 10x12 with a Sunray Probe mounted on it, so swinging a heavy machine is normal for me, so I was a little surprised when I had to switch back to the stock coil after 2 hours.