I am not in the same league as the others, but my advice would be if your determined to buy, then buy the very best you can afford.
I have only used one of those mentioned, I had the BH ID. It is a good machine on the beach and in shallow water. You just have to be very careful with it to be sure you get a good seal when you replace the batteries, no sand on the O-ring.
BHID is a good unit on the beach and the leds help identify what you are finding. I loved mine, ...........till I tried an Excal. I wish when I bought my BH, I had just put the cost difference between the BHID and the Excal on a c.card and sprung for the Excal to begin with. I may own other units, but I will still have an Excal with me.
I have never used the Tesoro but I have heard a lot of good things about it. You can't help but like the lifetime warranty.
One other bit of advice, I bought my BHID from Kellyco, but
my next unit will be from TonyinCT. He has spent far more time answering my multiple questions, being honest and trying to help me, (and I haven't bought anything from him yet), then Kellyco did when I was in the store with money in my hand. They sold me the Beach Cobra first

and I returned it.
You can trust Tony to be honest and give you the best deal for your money.
