I had the dreaded code 10 problem with three different cards (one from China, two from a US seller). I did a bunch of reading on the web and it seems that there are different versions of the 5300. If you get one that's designed for a specific brand of computer, it won't work in our Mini 9s and you get that code 10 message.
I have ordered a Dell-specific 5300 card from ebay. It's more expensive than the others I tried (not quite $40, including shipping), but if it works, I'll be happy. By the time I lose shipping to me and back and the cards I've had to return, I'd have been better off just to get the Dell card.