Just for my curiosity: Would it be better to have a soft shackle with lower rating then your snatchstrap or higher? In other words, which part do we want to fail first? The strap or the shackle. In case of a metal shackle I think I would want my strap to fail instead of the shackle because that would be less dangerous. But what about when we use a soft shackle?
In my experience, I have seen shackles failing the most, followed by recovery straps/winch cable. This is probably because a) very few people use rated shackles and b) many a times, shackles are put into the recovery point in such a way that the shackle bolt takes the contact with the metal recovery point, and hence takes the load at its weakest link.
Moreover, we talk about shackle risks more often because the broken pieces of shackle fly like bullets and are prone to hit people in all directions and that too far away from the site of the accident . A broken strap can also be fatal if someone is standing within its range, but this range is limited to the length of the flying strap. Therefore a broken shackle is potentially more dangerous than a broken strap. A soft shackle is also prone to breakage if stretched beyond its capacity but doesn't hurt anyone except the pocket
of its owner.
In any case, what fails more often doesn't and should not matter. Our choice of equipment should be such that we have enough margin-of-safety in terms of load being pulled. From this angle, both shackle and strap should be rated for a MINIMUM of 150% (preferably 200%) of the all-up weight of the stuck vehicle.
my 2 cents on the subject