Once upon a time I had a goal to purchase every set of irons the Hogan Company made. With the added guideline that each set I purchased had, not only matching serial numbers (such as the number you found on the ferrules), but also had original grips.
I have a few set of Power Thrusts, I didn't pay more than $175 for each.
As mentioned, eBay is a great tool for finding a resale value for whatever someone collects. If you have an eBay account, log in. In the search bar type in the set you want to sell. From there you will find another tremendously helpful tool. Click the box to search "Completed Listings". You'll be able to scroll through other eBay users whom have sold similar sets and what they sold their sets for.
While I have been out of the hunt for a number of years, I still have most of the better sets I purchased. And as a collector, I cant see a set other than one totally untouched, going for more than $200...
As a general rule, 3-putting is the worst feeling in golf.
That being said, as much as I HATE 3-putting, my worst feeling in golf came from by way of my 2nd shot on a par5 with a 3wood. A shot struck way back in 2010 that, although I've moved on, and have hit tons of monster 3 woods on par5s since, haunts me because of its significance.
I was in Thailand playing my first ever QSchool for any tour, in this case, The Asian Tour. I squeeked through the first round right on the cut line (-3). I shot Even in the first round of Final Stage and now I was on 16 of the second round, still at even, and had three holes to play before facing a cut, which I figured at -1, to advance to play the third and fourth rounds and secure my card.
I was no more than 230 out, so I figured, I can bunt this 3 wood either on the green for an eagle putt or close enough to chip in, or at worst get a birdie.
Then, I had my worst feeling in golf. I flared my 3wood way out right, my shot hit that STUPID palm tree. It didn't kick OB, but from 160 out, I was totally deflated and carded a bogey 6.
I parred in to post +1 after two rounds, and wouldn't you know. -1 was the cut.
Hitting that palm tree still delivers a chill. But as a silver lining, I think back and reflect that that was my first attempt playing in something that big. Not to mention, although I have a few friends that use the Asian Tour as their stepping stone. I know even more friends who didn't get as far as I did.
Rather than focusing on the length of a missed putt, I'd like to offer a different point of view, while staying in the genre of the most demoralizing shot being a putt.
Having to take a third putt, THAT, is the most demoralizing shot in golf.
F 3-Putts! F them right in the A!!