Research the machines that will meet your specific needs and hunting style. Pick one that fits your personality.
Jane and I have been hunting a saltwater beach almost every day for 2 years. She uses a Fisher Impulse (PI) machine and loves it. It is a very tough, simple machine, easy to use. She hunts helter skelter all over the beach: wet and dry sand, and some times knee deep in the water. She moves very quickly covers a lot of ground, and likes to dig lots of targets.
I hunt with a Sovereign Elite (tone ID) and am more methodical (Jane would say "anal"), following a search pattern, and carefully listening to each target before I dig. The Sov (and Excal) take time to learn, and the Sov requires a bit more careful handling than the Impulse. But I like having a pretty good idea of what I have found before I dig. Different strokes for different folks.
Curiously, after a few hours hunting, we both find about the same number of coins and rings. Over the long haul, we both find about the same number of goodies. I am slow, but she digs more trash. And Jane has found digital cameras and cellphones, things that I would consider trash and not dig. But we both enjoy the hunt, the exercise, and the beach at sunrise.
Good Luck
fod