Stainless fasteners are the worst. My company builds food equipment so they're a necessity, but... ugh. They gall terribly and they're squishy. If there happens to be a burr or crud in the threads, you might as well grab your angle grinder and drill, because that screw is not going to come out any other way.
It's interesting you say that, because I had a good experience with stainless!
I used to use a lot of stainless bolts on machines that went into hostile[1] environments. We used a variety of hex socket bolts, with thread lock compounds and calibrated torgue drivers to put them in and uncalibrated drivers to take them out when they eventually came back for refurb.
We rarely had problems putting them in or taking them out.
I don't know why problems were so rare. I think it being a safety critical industry helped: we bought expensive bolts and tools, and people had some training to use them.
