Not as large as many Tyrannosaurus fans think it is.
The ~1.5-meter reconstructed skull seems to be exaggerated, reconstructing it like a normal Tyrannosaurus skull actually gets it down to ~1.34 meters from snout to the quadratojugal.
It appears that agrees with this: comments.deviantart.com/1/1241…
So how large is this specimen? Well, it is pretty similar to AMNH 5027(they were both assigned to "Tyrannosaurus X"), so it seems to be a good base to use.
And here's the result:
It's still one of the largest known Tyrannosaurus specimens, but due to it's more gracile build, still smaller than FMNH PR2081.