FWIW, I had an issue with a FastTech order recently.
I ordered about a dozen products, and one of the products was shown with an availability of a few days instead of “in stock”. A few days later, they sent a message saying they had shipped everything except that item, and would send it when it became available.
About two or three weeks later, FastTech contacted me again to say the item had been discontinued and they had sent me a refund for it. Paypal confirmed the refund.
The in-stock items arrived reasonably quickly considering where they came from, but my local post officer apparently lost or mis-delivered the package so I had to file a case with the local postal system. A few days later they found it and delivered it. That’s not FastTech’s fault though; this particular post officer seems to mis-deliver things pretty often.
In any case, I didn’t ask them to ship the available items first… they just did it and let me know afterward. And I didn’t ask for a refund. Again, I found out afterward. It was kind of a nice change, since it seems people usually have to go through Dispute Hell whenever anything goes wrong.