I seriously recommend not using chain for any sort of truck-to-truck recovery, for the sake of your own health and wellbeing. I've seen a window get destroyed as the broken chain wizzed into the back of the passenger seat of a truck that was trying to recover another. Surely people have died or been seriously injured because of chains.
With that said, a properly sized chain is just fine for winching or using comealongs since you're not putting any impulse on it. I agree that twice the vehicle weight will be sufficient for this type of recovery. Any more is just a waste of money and weight.
For truck-to-truck recovery, I recommend a strap and some dead weight in the middle (in case a recovery point fails). For this type of recovery, you could see up to 4-5x the vehicle's weight in the strap for a short period of time. I've personally broken a 30k strap pulling someone out (granted, it was pretty old and beat up) and seen numerous 20k straps break. I've jumped up to a 40k strap and haven't had any issues with it since. For most of you a 30k strap will do very well and last a long time. I'd probably have replaced the 30k strap I broke with another of the same size had I not gotten a killer deal on the 40k strap. Another thing is to make sure the strap gets cleaned each time it's dropped in the mud. The sand/silt can eat away at the nylon strands and weaken it.
For the dead weight, I use an old backpack with some gravel shoveled into it. This would easily stop a d-ring from becoming a projectile if a recovery point failed. If the strap simply breaks, there's not really an issue as it's mass is low enough that even if it hit someone in the head they'd probably remain conscious (though it'd sting pretty bad). In a pinch, a gallon of water, another strap, a jacket/blanket tied in a knot, or any other somewhat heavy but loosely attached weight can be used as dead weight.
Of course, as with all recovery, if you're not inside the vehicle, remain a safe distance from the recovery operation. Seen people get knocked over by wayward straps (a vehicle slides sideways and takes out someones legs) as well as numerous straps break and one time, a chain. Thankfully none of these accidents have caused serious injury.
Be safe out there!
Edited by DMANbluesfreak, 20 December 2013 - 03:35 PM.