I received my new sef coil today. I went to the park i always go to. For the past week i have been covering the area with the 9.5 coil. Anticipating the SEF i wanted to compare the two. Right off the bat I dug a quarter at 5 inches. The area has been well covered by the 9 but no signal until today. This evening I went to the beach and picked up a quarter at 8 inches and another at 13, yes 13 inches. I almost gave up digging. One thing I noticed is that the depth seems to be off. I mean, when it says 2 inches it may be 5. The 13 inch quarter said 7 inches at first. Coil seems quieter and real smooth. I really like it so far.