I do mostly relic hunting and bought an F2 as a first digital detector about 4 months ago, (been hunting with a trusty analog with different size coils) and also bought a 10" coil from a web site at the same time. Am impressed with the depth and target separation of the 10" coil. Have not been disappointed yet, well, one time, when I went out for three hours and did not find a single keeper. But, I went back to the same place the next day with my analog and didn't find anything either! With the F2 and 10" coil I've recovered several Civil War bullets, shell frags, and a couple of flat buttons. Even some old coins at a 18th century house site - including an 1820 Liberty large cent. Haven't used the 4" coil yet. Will be looking forward to seeing how it does closer to the house. HH