fred, are your aftermarket parts usually from a chinese maker? I have read that, chinese factories with German-inspected ISO certs are OK, but the Chinese ISO certs are suspect. Adds to the risk of non-Japanese part purchases.
aftermarket here often requires some research, or, for many 'consumable parts' at least, avoiding the the very cheapest. No parts supplier wants to lose a sale because you went 2 blocks down the street to save $1.25 so, there's a bit of a race to the bottom. Those cheap parts often get purchased for cars being flipped/sold immediately - but a savvy buyer would avoid them for his own daily driver that he intends to keep. Oh, they may work well-enough at first, but may not be long lasting. Plus, we may have dozens of 'brands' to choose from, that makes it a bit tricky as well. The actual number of factories building the item may be small, but it seems a lot of companies are convinced they can make money with the right packaging and marketing approach. We must have 60-80 brands of batteries, even though there's only 5-10 manufacturers (w'ever - made-up number lol!)