A few years ago I was looking at the Mooer Elec Lady and Blues Crab, read some stuff online and some claimed to have opened them up and at least in some cases they are the same pedal.
There did seem to be evidence that Mooer branded were better quality or had less problems.
Might not be that Mooer is older as much as that they have better quality control.
The problem with Chinese production is not that they can't make great stuff, it's that they can make the same stuff cheaper by somehow cutting costs, I'd guess with cheaper inexperienced labor, speeding up the line, using substandard parts in a cheaper run, anything that can save a dollar on a pedal means ten or twenty dollars lower retail.
There is even speculation that substandard batches of Moore pedals have been branded Donner.
Must be assembled boards of course, loaded into Donner cases.
Donner must also have standard runs, even if in the same factories as Mooer, or on the same board design.
But much of Chinese production gets many names applied.
I did buy an Elec Lady and it's a decent pedal.
Seems like prices go up with popularity and down if they don't sell well.
Chinese markups may have nothing to do with margins.
Likely a $3.00 item sells profitably for $20 or $60 if the market will bear it.
Search and you can find those Chinese pedals for that broad a price range.
Moore maybe $30- $80 retail for the same brand new pedal.