The Tron's not bad but most of my phono stages are considerably more accurate still than that.. +/- 0.05dB in most cases though I normally quote it as +/- 0.1dB
I'm afraid I'm not about to go through the measurements again to make them into pretty graphs though!
It needs to be born in mind though that a reverse RIAA eq network must be used to generate an inverse curve against which to measure the RIAA accuracy of a phono stage. this network must itself be very accurate indeed of course. I guess it could be generated digitally nowadays but I'm a traditionalist;)
I rather doubt that the tiny inaccuracies of the Tron's eq would be sufficient to have any but a very minor effect on it's ability to reproduce a squarewave. As an aside here, if you pass a squarewave through a reverse RIAA generator (awkward it itself as a certain amount of HF bandwidth restriction must be used otherwise it will try to produce infinite treble boost!) and then feed this through a phono stage under test you should then see a squarewave out... the degree to which it's not square reflects the RIAA accuracy and it's a great quick test that it's in the right ballpark.