Quoted from G-P-E:
Those parts are just as bad - they are blatant counterfeits and ST would be real interested in that one. Really importing those by the case?!?! Takes balls bringing those in through customs -> with the right customs agent, a case of those can be accompanied with a $2M fine ($2M for an individual, $5M for a company) plus up to 10 years in jail. I would really think twice about ordering from that source.
ST discontinued 2732s long, long before 2013. They are blatantly taking some parts from 'somewhere' and marking them with the ST logo, part number and selling them as new ST parts. That clearly qualifies them as counterfeit parts.
Those could be 'fell of the back of a truck' parts remarked to make them look like STs. Or maybe trash canned 'failed functional test' parts. Or ... who knows.
When we made parts (yes, unfortunately many were fabbed in China) - functional test was much more stringent than what we pinheads need for our uses. Most "failed" parts would pass what we would consider functional but will fail by small degrees in areas such as access time or power consumption. At the time, more and more of our failed parts were somehow making their way back into the consumer market. To curb this - we had to shred failed parts that were made in China, Korea, Singapore and other far east countries. We still had many parts fall off the backs of trucks. They would ship 100K of one part... and we would receive 95K. Happened quite often and nobody over there gave a fat rat's patootie. "Huh, well... we must have miscounted."
If the Chinese were smart about this - they would sell them under their own name as new parts. Nobody could contest that. New DingDong brand parts would be better than mystery counterfeit ST parts or no parts at all.
I guess box is a better description. 300 or so. First time i ran into those China eprom clones was actually came from an often recommended domestic seller. It was pretty obvious something was up when they are marked M2732A, say PGM at 12.5v, and you need to PGM them at 25v. At 21v they program really slow to the point it is suspicious even tho the data sticks. No problems erasing and re buring a few times at least at 25v.
Most stuff im making now is using bigger sized eproms and luckily legit new ones are pretty easily found. But for old boards that want a 2716/2732, its easy for a hobbyist to snag the aliexpress ebay special. Scraping off old labels, erasing them, bent up legs, then it turns out the chip won't burn... no fun. One time programmables are fine for most purposes. How often are you really going to change the ROMs in a pinball board.