The Coil your referring to is a NEL tornado Coil its made in Russia or the Ukraine .One of those anyway..
The Ace 250 as far as I`m lead to believe, is not that good on wet salt Sand ,but does better on dry sand.But if you ring up Regtons ,I`m sure some one there will confirm if its good on wet sand as well as dry , but from my listening s they are not liking wet sand as they don`t like the salt.
The coil can work better on dry land though, but don`t expect double the depth from it over the stock coil . You might get an extra couple of inches if you get an exceptional lucky break at some point. What the bigger coil will give you, is a bigger footprint of area coverage mainly. You undoubtedly will get some folk who`ll mesmerize you of tales of 6 "- 9 " extra depth, but its very often wishful thinking or its been in the side of the hole when digging and when they`ve missed it and gone deeper they very often through soil disturbance fall into the bottom of the now much deeper hole and are then seen , and the coin is then seen as it has come from the depth they went eventually down to ,when in reality ,it was probably only two inches down at the side of the hole, in the first place .
Unless stated in the sale of a new or second hand Garrett Ace 250 as having one included, the Pinpoint probe you have to buy separate.