Snookie very hard question to answer as every machine is built for a purpose. we don't use Gold machine in water, nor do we use coin machine in goldfield. most machines are design specifically for one purpose some may be good at many type of detecting but not excellant at any. Some discriminate others don't. My opinion is as follows
Gold, Minelab GPX 5000.
Coin, Minelab CTX 3030, Garrett AT pro, or Minelab Xterra & many others depending on price.
Waterproof machines Whites surf, Garrett Infinium, Garrett atx, Minelab Excaliber.
Then we have some machines that can do some Gold, Coins, or beach like The CTX 3030, Garrett atx, Plus some shortly to be released but again it still comes down to cost.
Gold, Minelab GPX 5000.
Coin, Minelab CTX 3030, Garrett AT pro, or Minelab Xterra & many others depending on price.
Waterproof machines Whites surf, Garrett Infinium, Garrett atx, Minelab Excaliber.
Then we have some machines that can do some Gold, Coins, or beach like The CTX 3030, Garrett atx, Plus some shortly to be released but again it still comes down to cost.