I use chains on a very irregular basis, 5/8" fo rme. I've found that long term they wear me out. And long term being anything over about 8-10 weeks. I'll only do that once per year. You want to hang the chain from smaller chain that you actually drape over the bar. The bigger chain need to be set that so when you are at complete lockout they just have a couple inches on the floor to minimize any swinging. When the bar is on your chest you will want all the weight of the bigger chain on the floor.
Even though it really isn't that much weight it really wears on you throughout each set and will make you focus on push through to lockout. If one is becoming somewhat advanced and has a sticking point 1/2 or farther up, this will make a big difference.