Amazon is selling a $50 Champion duffel bag for $20, and shoppers say it's 'lightweight but roomy'

TheStreet aims to feature only the best products and services. If you buy something via one of our links, we may earn a commission. If you're even a little bit active, sooner or later, you'll need a good way to lug your essentials from home to the court, field, track, or gym. And even if you're…