I bought and used Tiger Shark and was having trouble with it (it was contantly making at tone like it was finding metal---beeeeeep). I called and spoke with James and tried to trouble shoot it over the phone. We could not fix it over the phone. He said to send it in. Two weeks later I got it back. I called and even asked how much do I owe you. He said "nothing, its free."
That conversation and that great customer service sealed the deal in my mind. I will always buy Tesoro because of the way that he treated me. My only complaint about Tesoro is that they do not sell other things like clothes, food, etc. Could you imagine how happy the world would be if there was a chain of Tesoro stores.