I personally think you will not find much difference in similarly sized coils, as long as they are a well known brand name.
I like my NEL coils (Snake and Hunter) and people seem to like the NEL Sharpshooter. I like their price and how they work.
If I were you, I would look for the size coil you want from a known company and has the lowest price.
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Fisher F70 w/Fisher 11” DD and NEL Snake Coil
Fisher 1280-X w/8” Coil
Fisher F2 w/4”, 8” and NEL Hunter Coil
Makro Pointer
Killer B Stinger Headphones