J-Dude, the only tough part of your request is giving advice on salt water beaches. Unless you are using a pulse or dual/multi frequency detector, the wet salt sand is going to play havoc with your detector. There are a couple of single frequency detectors that seem to do well in those environments, like the AT Pro or the G2 made by Teknetics, but they are the exceptions to the rule and outside your budget of $300.
You can use the Ace 250 or Delta on the dry sand no problem with good results, but you will need to crank your sensitivity way down in the wet sand. You will sacrifice a lot of depth in the process.
As to which you should get, I would give serious consideration to the Delta. There is a gentleman named Monte who posts on various forums and is extremely knowledgable. He lives in Oregon, near your neck of the woods. In that kind of soil environment, he has a very high opinion of the way the Teknetics machines work out there and he has high praise for the Delta.
I believe he posts quite a bit on Findmall, so you may want to take a look.
Soil conditions around the country obviously vary a great deal, and not all detectors work the same in all environments. That is something you must take into consideration no matter what you buy.
If there is a club in your area, I would get to know those folks as they can be a great help.
Good luck on your final choice.
