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Never mind, I'll save you the trouble. The 1236-x2 is a lot better at relics and coins and can be used on salt beaches and heavy mineralization. I'm told it even works well on these crappy beaches here in Oregon! The Ace 250 does not and will not. Budget Tesoros work very well there too, better than the high priced ones such as Tejons and Vaqueros.
The Ace 250 sucks in all the above, especially in bad soil. It works ok inland in some places though, as long as the soil isn't too full of magnetite, hematite, or iron junk or hot rocks. It's too noisey there. The Ace works pretty good as a door stop in a closet though, and if you want to try your luck at figuring out if a coin is a dime, penny, or a piece of iron, then the Ace is right for you. The Ace is a toy. The 1236-x2 is not, and it has a very good silencer mode too..
I think the Fisher F-2 is the best thing on the market now for the money though. It's a real honey, very lightweight, and costs only $199.95. It has lots of toys too, and comes with two coils.
Check my posts. You'll see my review.