I guess I'm one of the lucky ones ... I have a pretty good collection of stuff and not one regretable purchase. I do regret a few sales though (I have since vowed to never sell a gun again unless it is directly related to the purchase of an upgrade/replacement). I also regret not picking up that Stainless Colt Python for $800 the second I saw it ... because the guy behind me did 2 seconds later. DAMMIT!
I dont usually impulse buy and I research what I want so when I make a purchase, its most likely going to be one I'm happy with ... with firearms anyway ... I have made a few "regrettable" mistakes in other areas however.
I rarely regret, but I was not happy with a SW-60 357 snub. I found it a little obnoxious to shoot. I did carry it for a year till I bought a p239 that I've carried for 12 years, well till I moved into Maryland lately.
Anyway, I was tickled a couple years ago when a buddy said he was looking for a snub nose 357. I showed my 60 to him, and he offered to trade me a new in box Winchester 94 rifle. I didn't hesitate. All good!
The only time I let a gun rag influence the purchase of a new gun was a S&W Sigma380.I wanted something small and user friendly for my wife. It was not what I hoped it would be; should have spent the extra $100 and got the Colt Mustang.
I have enjoyed all of my purchases up till the last one, and I do not even have it. My paperwork has been lost and I am in 50+ territory, but hey I am on the fast track now.
Most frustrating purchase was a old browning safari grade. The scope was frozen/shot and could not figure out how I was all over the place trying to sight it in. Once figured that out love the ol gal.
Not one I bought, but wishing my grandfather had kept all the guns he told me he sold in 1919 when he got married. Said he didn't want to have guns in the house with kids around (sigh).
Rossi .410 youth four days ago. Impulse buy for my child passing hunters safety course. Should've bought her a cricket for her size. I left it in the box and she probably won't fire it till she grows a few more inches.
I regret my 7th wife, bought her with a half pack of Salems, soggy Hershey Bar and a felt tip pen in Somalia. We divorced when she said she wanted false teeth, no teeth was her only good point.