Swivels are fine but like anything there are good and there are bad ones. Force is a chinese made brand and the exact same as quite a few other brands, which all come out of the same factory. They are one of the better lookers but sadly one of the worse structurally, so what Charon experienced doesn't surprise me. Sad to say but he's one of way to many to have that same issue with those ones.
Stainless is also fine in a 'anchoring' system but not a 'mooring' system. Again that's well proven. To become an issue it needs to stay submerged for a while continuosly
. Up and down as happens with anchoring
is fine. But again it can pay to watch for real stainless and asian stainless, the real stuff is the better choice. The main issue SS has is how it can be messed with by problems on the boat like stray electricity drifting around, that doesn't happen to steel, it can but nothing like the degree it does with SS.
For the SS to go bad it can't breath i.e. don't leave submersed continuously. And to get dissimilar metals you need an electrolyte i.e. salt water
. Anchor up on your bow means the SS can breath and no electrolyte so all is good.
Most shackles are now made in china. Most of the ones that aren't are stainless or genuine Green Pins.
As a general rule
rigging shops tend to be more china than a good chandler, or they are here but it maybe different where you are. If you have the chance go to a place that supplys the big tower cranes of the 'over head
lifting' industry. They have massive safety
restrictions which are generally very well enforced so they will have to be more anal about the gear
they sell than others.
I buy and sell around 50-60,000 shackles, assorted, and around 1000 swivels, assorted, a year. I must admit it is very hard for a boater to know just what they are being offered a lot of the time as most selling them have no idea what they are selling. Also the level of marketing
does mean the truth is often a casualty.