The Tiger Shark is not my first water detector from this company. My first was a Tesoro Sting Ray II I owned for about 15 years. I finally sold it as I wanted a Minelab Excallibur II I still own the excallibur but I missed my Tesoro for fresh water hunting.
I have found the Tiger Shark to be a little different the my Sting Ray. It's more responsive on small Gold and silver items and is a little more chattery on small iron like nails and wire. I am getting used to the sounds now and am finding jewelry right off the bat. I already have two Golds, a 10K Bengal ear ring and a 14K woman's ring. It also found a very small Sterling ear ring with a junk stone in it.
Un like the Excalibur it will find Gold chains and very small Ear Rings. I have found that on iffy targets like gold chains if you will just speed up over the target, if it is good it will improve in sound, if it is a bad target it will break up really bad.
If you are hunting fresh water it is a hard machine to beat, especially that life time warrenty. By the way the Sting Ray II I owned for 15 years never gave me a moments trouble, and thats a lot of good to be said for any machine. Rick IL.