I tend to buy lifting slings for 4x4 recovery work. They have been tested and have a certificate of safety so they can be used for lifting, so you know they aren't just any imitation junk from China. They also have a high safety factor - i.e. if they are rated to 10,000 lbs for example, they are designed to fail under several times that load.
Similarly you can buy tested and certified lifting shackles. I've seen cheap Chinese ones just break in half, which can mean the other half and the strap are propelled backwards with huge force.
Of course, there is a difference between being towed on the road and someone towing you out of a ditch or a field where you are axle-deep in mud. The latter will need a lot more force. There is also the risk that whoever is pulling you wants to take a run-up, which puts huge forces on towing equipment and can lead to dangerous sudden failures. I know many 4-wheelers like kinetic energy recovery ropes - they act like elastic so the recovery vehicle can get some speed and snatch the bogged vehicle out, but in doing so they put immense forces on everything concerned and when something breaks can slingshot it with lethal force. So I personally stay clear of them.
Steve.