Hi Lee. I get a median of about 2.2 arcsec, with some nights up to about 4 (eg last night). Have occasionally had seeing down to ~1.5 arcsec. None of this is corrected for elevation angle.
this is a bit worse than Racine suggests (from large scale surveys) for sea level conditions (I am at 22m ASL). "The median ground‐level seeing at zero altitude is 1.97. At 2500 m altitude and 10 m elevation—representative values for many telescopes—the model predicts a median DIMM‐scale seeing of 0.67...It is remarkable that a knowledge of altitude and elevation alone suffices to “predict” the median seeing to an accuracy of less than 0.1". So the best possible seeing can be predicted by your altitude - at Kilcoy, median seeing below 2 arcsec should be possible at the zenith - are you in a built up area with local thermal turbulence?
another possible complication is that CA in your scopes might contribute some star broadening. If you need to refocus on filter change (assuming parfocal filters) or if your NB data has smaller FWHM, then CA could be an issue.
ref:
http://www.jstor.org/stable/10.1086/429307