Add my experience with Troy @ ProSpeed Racing to your list.

Approx 18 months ago, I ordered an electronic boost controller via his website and paid with Paypal. Few days later I get a full refund but no communication as to why. I emailed him to query and he replied stating the item was end of life and no longer available. To his credit he offered me a better product for a discounted price which I purchased....

and then waited....

and waited...

and emailed him for follow up with no reply. And this went on for a week until I had to write in an email that If I don't get a reply I'll have to lodge a dispute with Paypal.

And then he replied, and then shipped the item

The original EBC that was end of life is still on his website for sale, 18 months later.