The ones I bought from the dollar store were really thin and cheap, the stitching on the top channel is all frayed, and they feel like they might rip too easily.
The same thing from Walmart is only a few dollars more - you can find them in the aisle next to the plastic laundry baskets - and is much more heavy duty (comparably). Makes me feel a little better about keeping such an expensive piece of gear in them. Maybe it's just psychological … but an extra $2 is worth the peace of mind, at least to me.
YMMV
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