I've a similar meter (it may be the same, but it's in a very inaccessible spot in the spare room right now so I can't check). It seems as accurate as the built-in meters of two early 80s cameras I have. What are the odds all three are off by the same amount?

It is a very nice meter, though if you are not in bright light, the dials can be a bit difficult to read (in other words, I may need bifocals).