Personally, I would not buy any of these 4,000 guns. In my mind, they are radioactive dog mess.
If I were in the market for a MG and I had the choice between a
true transferable that was made in the states and registered before 1986, like a Vector UZI, or a Mod A conversion, or one of the newly re-classified, pre-sample/now transferable, imported factory IMI UZIs, I'd buy the ex-pre-sample. Even if I had to pay a third more.
I'd do that happily.
Even knowing full well that the transferable classification could change at any minute and devalue my UZI by more than half, that wouldn't deter me in the slightest.
Because I don't buy things like firearms for investments, I buy them because they are fun and cool. And I don't want look-a-likes or clones, I want the "real deal".
If I want a 1911A1, I'll look for and buy a real US military one, even though I could get a brand new Tisas 1911 clone that's just as good quality and appearance wise, but for 10% of the cost of a "real" one.
Since the difference between a pre-sample and a post-sample is that if you structure your license correctly, you can keep your
pre-samples after you drop your SOT, and there is
no way to keep your
post-samples after you drop your SOT, it makes the risk more tolerable.
So if these pre-samples that became transferable were sold to individuals, and the ATF decided they made a mistake, the chances are very good that the new owners of them would be allowed to retain them and the only difference is that when/if these new owners decide to dispose of them, they could only be sold and transferred to an active SOT.
Unlike if this happened with post-samples. In which case, the new, non-sot owners would most likely have to destroy, surrender or sell them to current SOT licensees.
So in my case, as someone who would love to own "real deal" MGs, I would
definitely take the chance and buy one. Because, as I said, I'm not getting one for an investment, nor to hand down to my heirs. So I don't care what the value or transferable status of it is in the future. I just want one for my own amusement.