In general, a guiding < 1 arcsec is fine. Anything below this value is almost invisible when using an average telescope.
Guiding is also not only dependent on your mount. Seeing and polar alignment also play a major role, as does the pixel size of your guiding camera. I also use an EQ6 and my results are around 0.8 arcsec RMS. So that's pretty much the same.
Much more important is to know the FWHM and eccentricity: these generally determine the quality of your lights. In Pixinsight you can easily examine all taken lights with the Subframe Selector function.
You will see these types of graphs and from this you can determine which lights you do not want to use any further.