Sag.,

I have also heard of the two year recommendation and plan to follow it whether it is true or not. This is one area where it definitely is better to be safe than sorry.

I just replaced the chains on my API Bowhunter after two years. Cost was $35.

The original chains came with the black rubber coating on them. It wore through in the center of the chain, where most tree contact occurs, before the end of the first season....though I didn't notice any increase in noise or damage to the tree.

The new chains came with a different form of semi-transparent brown coating which seems to be thicker and yet still as flexible. I have used it twice so far with the new chains/covering and have not noticed any wear whatsoever.

Hope this helps.