issue with Porsche 914 speedo readings

[itHaKa]

thank you guys,
will send an email to North Hollywood Speedometer to see if they can help , the problem is that i am from Argentina,
and i am not sure if i have to send them my speedo..
about the safety feature, not sure, because running at 30 km/h , it still shows 40 km/h, so error is > to 10 %,
i didn´t test the accuracy of the odometer yet ,

for the 914 speedo users ,i know there are a lot ,like sandeep, aartjan , and other users :
is the speedo working fine , is it accurate, no issues ?