The unfortunate thing is you can't easily tell the quality of something by looking anymore, even by price. Also brand names have much less meaning these days as almost all are licensed to Chinese manufacturers. Brand X part number Y could be manufactured by one plant on one day of decent quality, and the next lot comes from a different manufacturer and is complete ****. There are examples of this everywhere. There is also documented evidence of Amazon and Wal-Mart etc positive and negative reviews being bought and sold by overseas mass-review-writing firms. The "UL listed" hologram tag is easily counterfeited and there is documented evidence that counterfeit "UL Listed" items are sold by nationally known retailers every day. So everything is a crapshoot.
Most users of this site, myself included, would pay more for a quality piece. The problem is, where do you get a quality piece? (True for almost every consumer good these days.) The $50 cord could very easily be just as good the $100 one, or even better.
In my opinion the options are 1) Buy bulk good quality #10 SOOW-A (or similar SO cord) and brand name connectors from a local electrical supply house where you can be sure you are not getting counterfeit and spend $100-150 building a cord that is flexible in all temps and you can pass on to your grand kids or 2) as was already said buy the cheap one and enjoy it, repair/replace as needed.