Like the snatch blocks, I don’t think I’ve ever seen pictures of yours that showed you using them.
I've got a bunch at the shop. Its just really rare that I can't do the same thing by just putting a nylon or steel choker, basketed through a shackle. In this occasion, I needed to hook in two spots and knew the angle relation would be changing, as we went up and down a bunch of times. So snatch block it is. Most of the stuff I end up picking up doesn't have to change relation as its being picked.
For trusses off the spreader in a 4 point, I'd rather do a nylon or steel through a shackle because then it isn't constantly rolling back and forth all the way, I hate it when they take one line off, and it rolls all the way over and smacks someone. And then its all the way up at the block and you have to pull it back over to hook the next one up. When you come off the load with a nylon basketed, it will kind of hang where it needs too for the next one.
Most of the tanks I stand, I'll just 4 point pick them and let 2 carry it when starting up, they end up hanging level, where as if you have a block, if there's a ladder and hatches on one side they will hang all wonky.
And for lifting skids and such, they are too often out of balance, so putting in snatch blocks may even out the tension on the cables, but you don't have any way to hold it level. 4 even sized chokers, and you can add and subtract shackles or even roundups and get a skid to hang halfway straight. They don't have to roll once you have them up.
Mine mostly just lay at the shop. Probably the guys that use snatch blocks the most, are guys standing up tilt up concrete panels, that's the only way to keep from destroying them. But the pour in place tilt ups are really too big for the equipment I have, that's mostly crawler or truck lattice territory.
