I just put a NEL Sharpshooter on my F2 to try it out. It's kind of large for a “sharp shooter” (9.5 X 5.5 DD). But it is built better than the Fisher coils, IMO. Seem sturdier, the cord seems of a higher grade, and the plastic is light but strong. Even the design gives you a little U area where the two Ds meet where the PP has the target residing every time. And as noted above, even the bolt that comes with it seems easier to tighten and better than the stock Fisher bolt.I'm pleased with the build for the money on the NELs. It's just that for the F2 it's not a depth demon as it appears on other machines. Of course, what do you expect from a "sharp shooter"? I get signal on a buried quarter at about 8-9" in disc. But I can ID it on it's back at about 6-7". The stock 8" concentric did a little better by an inch or two.But I have only A/B them once. So, only having the F2 for about a week or so, I'm still playing and don't take my findings as what others may say that have been using them longer.