IDF Ching Kuo speed?

Hi all.

For about a decade, most publications and books listed the top speed of the IDF Ching Kuo as 1295km/h “at altitude”.

I see now that the Wiki article is now saying Mach 1.8.

The previously listed lower speed has always seemed laughably low to me, based on a variety of factors, and this Mach 1.8 speed on wiki seems like a far more likely speed.

Does anyone know what the true top speed is?