..I have 2 other PI's !
The thing I like best about it is, it's so simple to set up, you are not going to miss anything, and it does deep. Sometimes it's just fun to swing n dig knowing nothing is going to be masked. The main problem, like you are finding out, is in trashy, iron laden areas it's not a good unit to use.
Like I said, if there isn't much iron, but lots of other targets like lead weights, tabs, foil, bits of copper...you have to dig those even with a VLF or you will miss the gold and silver.
The only draw back of the PI is the iron. But the plus is, you can hunt anywhere..black sand, in the water, rain, etc.
When the weather is nice and the surf is calm, take it out in the water. There is where you will really see the difference since once in the water, there isn't a lot of trash. The coil will stay on the bottom, you can swing slower, take your time and listen to those soft rises in the threshold.
Don't sell it...give it a chance. One nice ring and it will have paid for itself.
JC