Yes, I have had this experience with Moniker and much more!!
First, the tasting program was presented very simply too me that it cost $.25 to delete a name, however they did not tell me that you could not get a refund out of your account and had too eventually buy the amount of domains you tested. So, without knowing this I tested 5000 names only to learn that I could not get back my $35,000. This is only the beginning.
Next, I deleted 1000 domains within the 4 day grace period and sat there as there system said this was successfully complete, however I did not check my record log to confirm this. The names were not deleted so I had to eat $7k of my credit.
Next time I tested 300 domains and thought I would get around the issue of potentially screwing up a delete, so I emailed them the list I wanted to delete and called to confirm they would delete it. Bottom line was they screwed up on the delete, and admitted it, but kept chanting their montra that you โtest at your own risk.โ