I've had one for a couple of weeks. My first, so I can't say a lot about comparison. But I found that it didn't take me long to set it up to ignore pull-tabs. So far, when I can discriminate between coins and small aluminum pieces, it does hit on large aluminum objects, like a beer can, but I'm beginning to hear the difference. I get very good rejection of nails and iron bits. In controlled testing, it does what it says it will do. Pretty consistent response to small coins, like pennies, at two inches or more in rocky soil. Pinpoints well. I can depend on a small object being pretty well center of the coil, within the small inner circle of the assembly, as indicated by passing over it in both directions. So I have to say that, so far, I'm pleased with performance for the money.
For the money you cant beat them, no bells or whistles but plenty of power.
Another good thing is the options. You can get a 4" coil for getting into tight places with a lot of trash and still focus on a single target, and you can get a large 10" coil for the really deep stuff good for cache hunting and virgin territory, all without spending much money.