I bought one for measuring small amounts of gold and silver. It functioned reasonably well for about a year, then it would not work.
I opened it up and looked at it. The battery leads were put on and designed in such a manner that they got shorn through and cut off by the plastic forming the case. I reattached them and it worked again.
It functions off and on now after a few tries. It is weird how they made these so rinky dink and cheap, and they cost so much money. I think it has to do with their primary market use, which is probably in the drug trade.
I just opened it up to see what was going on and one of the batteries seems to have had a electrolyte issue and seeped out a little, so I will have to get another 4 out from my car or somewhere to test it.
I bought mine off E-bay and it was I think a factory reject or return that they fiddled with and got to work. Badly manufactured. If one company could go in and make these reliable, they would make a name for themselves in the business.
So they are not that reliable. A postage scale would work just as well, not ever need batteries, and would not suddenly stop functioning for no apparent reason.