There's a good pound or more left of the merino I overbought before realizing I dislike matte textures. Once it's spun I can quit reproaching myself.
Mail order is great for handspinners but also tricky. You can wind up with items that are a pig in a poke. Sellers are reputable and honest, sure; judging items at a distance is difficult. I've misjudged more than fiber. I love books and I don't regret buying any, but since I get books about the fiber arts mostly second-hand on the Advanced Book Exchange, I don't always know how relevant and absorbing the content is going to be. I try to find copies to look at before I get my own.
I need to get another lesson on using hand cards so that mine don't feel like such a total waste. I much prefer using wool combs. Even though combs take strength and time, they cut through fiber easily. The little teeth on the wool cards, in contrast, grip and feel awkward to me. I am told this is because my technique is faulty. I knew I didn't get along with hand cards before I bought them because a friend let me try hers, but I ignored my instincts.
I got handcards because I had some idealized 1970s notion of handspinners all spinning lofty woolen yarn from fluffy rolags they handcarded. Reality is much different, with commercially-prepared roving or top very commonplace anywhere spinners gather and with combed locks or drum-carded batts a very distant second. You'll see the occasional basket of rolags at a meeting. I am just reporting what I see. I could be wrong about the popularity of fiber preparations. Perhaps modern handspinners all whip up mountains of rolags when they're at home.
The oddball purchase that surprised me is the cheap spindle I call my "nerd glasses" spindle because I taped it up where it broke. I use it more often than my prettier, better quality spindles with their custom hooks and hardwood shafts. It has the light weight I prefer, same as them, and it is comfortable to hold. It has a larger diameter whorl, which is a positive. I would say I reach for it often because its cheapness and rough condition make me feel safe taking it places where it could be broken again or lost, but that can't be the only reason. I use it at home a lot too. I fear I am using it as a way to preserve my better ones. You know, the trap of keeping nice things stored for that golden someday, even though mañana never comes. Not particularly productive, and irrational. There are more nice spindles to buy if mine get wrecked from accidental abuse, and normal use keeps a spindle in perfect condition.
There are some supplies and tools that I haven't gotten around to trying yet, so I don't know yet for certain whether I am going to have serious buyer's remorse over them or not. The unused items bother me, but not enough for me to dig in the boxes and use them right this second. Some are for related activities like weaving. They will require me to learn new skills, which is why I put off trying them.
I have put them to some use: as deterrents. They serve as a precautionary tale to stop me from loading up on more. Fortunately, spin yarn long enough and you realize you're fine if you sit back and wait. More chances to buy are always coming down the pike.