I think if you open up the cheapies,you'll find they use a far from modern industrial process.
The important point is that mentioned in passing by alm,in that,it is a quite a small market.
Why tool up to make high tech cheap probes,when you could put that investment towards consumer stuff where you do have a huge market?
In the meantime,I suggest,buy the cheapies,& when they fail,as they will,replace them.
Keep the bits from the broken ones,though,as you may be able to fix the next one that fails.
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