What do you guys think about aftermarket coils? Like sef and NEL and sunray and the like. I bought a 10x12 sef from Kellyco last year and it was a piece of !!!!. Was blind beyond a 3 or 4 in of dirt. Tested it extensively in my test garden and it just didn't perform as well as my 11in pro coil that the etrac came with. Last month I decided to take another chance on a coil, and ordered a 13 in NEL tornado from the Ukraine. And I've only used it a total of about 8-10 hours, a few of which were in the test garden, I was hoping it would detect things at a much deeper distance than the pro coil, as far as I can see, it doesn't. It might be AS good as the pro coil, but I don't think it's better. Only time will tell the true tale. It performed well enough in the test garden for me to actually go hunting with it.