Well, I did win an auction (actually, a buy it now) for a very nice Flynn 63 boring head that I am in love with now. But that's a different story.
3 months ago, I decided I needed to buy an 1/8" endmill holder for the Sherline mill. I also bought a 3/64" EM to machine a small brass plate for my mother. The items arrived, but when I tried to spin the EM holder onto the spindle, less than 1 turn engaged. I looked more closely at it and realized that while the threads on the spindle extend 0.300", the threads in the holder didn't even start until 0.250". So, I sent a message to the seller and never got any response. Finally Ebay said to return it and they would refund the purchase price. Unfortunately, I had a couple of business trips and was out of town for a month so I didn't get it sent back right away. I finally got it back and decided that I would just make one. So, I made a threaded arbor for the lathe and turned my own holder. But I ended up with about 0.006" TIR, so I thought, since so many people rave about A2ZCNC, I'd just buy one from them. Went to Ebay and bought one and it arrived today. Stuck my EM in it and spun it onto the mill. Got a couple of turns of thread engagement, so that was nice. Turned on the spindle and OMG! Terrible runout! Took it off and put it on my threaded arbor in the lathe and confirmed that the holder itself has a little under 0.003" TIR, but the EM, which was pretty snug in the hole, has 0.018" TIR. Back to the mill and on the spindle I measured it at between 0.015" and 0.020" as well.
I sent a message to A2Z, so I'll see what they say. I am starting to lose faith, though. The best I can hope for is that they will just send me another one. If I have to send this one back, I'll have to pay another $5 for shipping. And if they refund my purchase price, I'll be out the shipping to get the thing, for a total of almost $15! All to learn that nobody can make a good 1/8" EM holder for the Sherline mill.