To those of you using "rods" are you anchoring both ends with stakes(I suspect T-Bars) or just the top end with the bottom end shoved into mud? 
I use 1/4" half round stock and make a strap on top of rod. My lock slides over the strap and I can use the same trap on rod or #2 twist-link chain. I can also cross stake with 2-24" 3/8" stakes if the conditions dictate this. Often one 24" stake is sufficent. Bottom end is just shoved into mud, sand or gravel.
Next question is for the latter usuage how long are your rods, do you have some type of flange/pc of flared metal, etc. on bottom end and what size material are you using?
I use a 8' rod for Beaver most often as they ride in the truck better. I have many 10' rods that I often leave at favorite sites in the woods on Private land. 1/2" re-rod works best. I weld a 1/2" nut 6" up from the bottom of the rod to keep trap from sliding off end.
Was thinking of making/using the cables this year but still am undecided. Mostly trapping coon and mink in mud/clay type stream bottoms. Very few rocks are around here.
A 3/8" rod works well for coon if kept 6-8' in length. Any longer and they get flimsy.
MTP and Cumberlands both sell Bauer's Lifetime system for those that do not have a welder handy. Very similar system and Yes it will last a lifetime!