Product review (4 stars): Hit and miss
Had one of these in the compactor that came with our house.  It lasted about 4 years.  Got this name-brand replacement, and it lasted like a month.  The handles broke and, more importantly, it just got chewed up in the compactor.  The old one had the same problems-but after 4 years.

They either need to make these things more flexible or less flexible.  They are flexible enough that they tend to collapse when the trash is mostly empty.  Then, when the trash is later full, they tend to warp with the compacting.  Worst part is, after warping, they suddenly seem to be solid, and they want to keep their warped shape.  From there you have to manipulate them back into a straight shape--and start the process over again.

Update: Got a replacement, and it is holding up MUCH better.  I guess it's hit and miss, but with Amazon's easy returns, you know it will be fixed.