I was aware of a chap who was rebuilding a series Land Rover & making a stonkingly good job of it too. This was pre mobile phones with cameras & he was proudly showing me his picture album which he took everywhere to show anyone that showed even the slightest interest. Over a pile of spares he was buying at our local Landy supplier, he announced that he had had some special windscreen hinge bolts made for him out of stainless. He’d taken all the Whitworth & UNF hardware out & replaced them with the nearest metric equivalent. I then ruined his day, probably a lot more than a day when he told me he’d replaced EVERY bolt in the entire vehicle with stainless.
I jokingly asked if he’d used stainless on suspension, head bolts & the like. “Oh yes everything” he answered proudly. “What” was the simultaneous gasp from all present ! There was then the crumping sound of a once proud man collapsing on the floor.
They might look nice but restrict them to things that don’t take the strain; under the bonnet possibly.
Some fancy bolt heads are pretty as well but if you can’t get the same grunt on them as you can a hex head don’t entertain them if they won’t take the torque.
Avoid at all costs any hardware that might be made out of anything other than quality steel; old battleships don’t make good screws, they probably fall short as fence posts.
M