It is useful when people mention issues with meters and at least give the test conditions.
The uni-t 90A is the one have "fusible" tracks ?
About the Little Brymen, even it has the components and layout, does it have enought to withstand a ESD event?
The Amprobe functional test either it could be related to a batch issue, improper use of the meter, so you could get one good batch, do a proper use of the meter and get a different result from the test.
[Edit]
The Brymen in case is the BM27s and it is similar to the Ambrobe PM55A, but the supplied leads are different, and brymen has protective caps on the leads. Doesn't change the test but changes the aspect in terms of trying to do it more safe to hands... yeah...