...Makes me think of the phrase, "Penny-wise and pound-foolish".Is the potential trouble worth the risk? Or i guess I should say, is saving a few cents worth the potential risk? This is one of those gambles where the odds of winning (finding good transistors) are very-high, but what you win is very-small. And although the chances of loosing are very-low, if you do loose you can loose big... maybe lots of frustration and wasted-time, maybe even burn-up some other good-parts. This the opposite of playing the lottery, where your chances of winning are low, but the cost of loosing is also low.Even in "big production" where the "pennies add up", it's not worth the gamble, because if 1% of your products end-up with bad transistors, it's going to cost you more than you've saved.Just for example, where I work (a small company), we almost always throw-away any parts that we've un-soldered. If it turns-out that part wasn't the problem... Maybe it's a different part, or maybe it was solder-short under the part we removed... We replace it with a new part from stock. Parts are cheap (compared to the labor) and re-using a part is just not worth the trouble. If it's an expensive part, it's probably something like a 100-pin IC. In that case, a few of the pins are likely to be bent, and again it's usually not worth the extra work & risk of re-using a part.
In "big production" ..., it's not worth the gamble
what you win is very-small
QuoteIn "big production" ..., it's not worth the gambleThat's true (or it should be, at least).But if you do not count labor cost in your hobby, it's perhaps different. After you checked the content of your surprise bag and verified it fits to your needs, you have added some value to those cheap parts.Quotewhat you win is very-small1.50 $ for 50 transistors isn't that cheap, IMO. Assuming you cannot really rely on the specs, but 90% will "behave like a transistor" and 10% die during the test... one should get 30 * "2N3904 or similar" for a similar price from a reliable source, IMO ...