I bounce back and forth but for some reason I like how the 15 Khz performs. It might be just a confidence thing beings my better finds came up using 15. If that makes any sense at all. Its kinda like fishing, I have my confidence lures/baits and have a hard time rigging up something different.

Garrett Apex, Nokta Simplex, Tesoro Bandido 2 Micro Max, Garrett Carrot