We found in testing a few months ago that the Gutter Critter Pro stretches about a foot and a half over time pulling it across the ground. This could potentially cause stress on the stitching, so we upgraded the stitching to a stretch stitch, shortened it initially by a foot or so after a few uses it would stretch to the full 12 ft.
We also removed some rocks and replaced them with a special mulch that soaks in some oils, yet acts much like the rocks in forcing runoff through the sponge and cuts the weight by 10% or so at the same time to guarantee there are no shipping issues with weight.
At Faythworx we are always looking for better ways! If you have any suggestions let us know!