Naturally I'm going to clarify right up front that I'm just checking it out, and definitely not planning to have it as a primary use detector for me. I have a couple of favorite models from White's competitors that work well for me and are in my Regular-Use Team, and my current main use detectors from White's are my XLT, modified classic ID, MX-5 and primarily the MX-7.
The Treasure series including the Master and Pro, are geared towards the lower end or entry level line. They're mainly designed for coin hunting but naturally could be used for Beach hunting as well. They are definitely not a good pick for serious Relic Hunting or specialty work such as gold nugget hunting.
In my opinion both of the models in this category should come equipped with a smaller size search coil. Most people who use them are going to be coin hunting and that will put them in typical Urban locations where they will be searching close to metal playground structures or metal poles and fences. Also areas that have a lot of discarded trash.
Not only would a smaller coil be more useful for trashier sites, but it would help the performance of these models when hunting any location where targets are more closely spaced because they have a lot of what we call "ring time" or delay lag time before they recover to respond to a nearby Target.
They work at about 8 kilohertz and share search coils with the Prism and recent Coin Master Series. I wish they had a smaller search coil in the 6-inch concentric design. To me the Treasure Pro has much more to offer in the way of features and performance with the tracking and lock track capability for the small difference in price.
As I mentioned, I've been checking this out as it was loaned to me, with the thought of adding a budget model to have on hand as a loaner unit for friends and family. I don't care for the oversized search coil comes with it which is really impractical in my opinion for a more budget priced detector that is hampered with a delayed recovery time.
You only asked if anyone has used it, but you didn't clarify what application or desire you had for the model in question.
Monte