It turns out, not as bad as I thought. Check out my latest video to watch me test 17 prisms, a bunch of which are Chinese fakes, & put one through a durability test to see if it fell apart after some minor mishandling.
For topo I'll run Chinese baseballs all day long. For precise control and monitoring it's nodal traverse sets. We run an a b c test and reject any target with identifiable error. It all depends on the task...
We run an a b c test and reject any target with identifiable error.
However by the time you've done this with a crew if you factor in charge out rates not much cheaper than just buying genuine is it? I know it does make for a time filler though if crew time already paid for a no job that day/afternoon.
We run the ABC test on the high quality prisms and usually bill it to the job we are preparing for. We also charge rates that cover any downtime.
I had a Topcon PS-103A that I was using with the Topcon 360° prism that came with it. It didn't maintain lock well. When I switched to a Leica GPZ-4 360° prism it maintained lock significantly better. It would be difficult to objectify the effect, but I'm convinced.
As was pointed out, some "chinese" prisms performed pretty well, others did not. But at the moment you click and send your money you don't know which you are getting if you are buying Chinese.
Finally, it could be that this big price advantage will be going away. Europe will probably, eventually, end up with a tariff deal. China may not.