=A0What a waste of time...and, of course, there's no ethical question here, either...
Ethical Question? Let me address that snide comment first.
Regardless the price offered by HFT, the tool is warranted to work as described and the offer provides for the customer's satisfaction with the tool for ten days or so. More often than not, the tool lives up to one's expectations and dies a peaceful death in the bottom of his or her tool box some distant day after the initial purchase and use.
On the other hand, the experience I read from the OP seemed to describe a situation in which the tool did not work as advertised, promised and warranted to.
So suggesting he return it to exchange it or claim a refund is hardly unethical one my part nor would it be on his.
Every such transaction include, in effect (an often at law) a contract between vendor and vendee and each has a right to expect the other will fully comply with the stated terms as well as any law (26 USC, I believe) that applies.
Last I checked, every product sold comes with an implied warranty of suitability for intended use (United States Code), though things may have changed since last I applied same in (Palm Beach, FL) County Court (Senf vs., General Motors & Adams Chevrolet).
As to the "waste of time issues, you may have a point. If you are employed and earning sixty-five dollars per hour it would be difficult to justify an hour round trip and visit to the local HFT much less an expected return visit to collect the refund as the cost in your time when added to the price of the discount item will likely approach the cost of the brand name gizmo.
But if the fine tool costs nearly ten times the price of the HFT competition and you're an average Joe who visits HFT as much for the pure shopping enjoyment and picks up generic stuff and expendables as well as "serious" tools, there was no "cost" to visit as you were going anyway. And the return-it visit is often combined with a special coupon or "deal" you've been waiting for.
As I said, my experience with HFT Return Policy has been favorable and they have often excused the delayed return when the item was in original packaging, in "as new" condition even when I could no longer produce the receipt.
If they had a "no returns" policy, they would go out of business in three weeks. The returns policy is part and parcel of their business plan and is accounted for generously under "Returns and Allowances."
I've several HFT tools about my shop that I seldom use. A Heat Gun and a pneumatic file come first to mind although there are lots of others that fit this category. It is likely that, were I employed in some way where the use of a heat gum or an air-file were part of my daily routine, these two would have been tossed or returned and fine replacements purchased at a significant premium.
You can't look down your nose at the OP for taking HFT up on their (well-advertised) offers.
If they offer it, try it. If it "works for you," keep it. If not, exercise the Returrn Policy clause in the implied contract and get a credit on your Mastercard.