I've had this set for a while using S-Video with no issue and recently RGB modded it (off the S-Board to SCART). It seems to work properly when the monitor isn't desperately changing its own RGB Cut off values high or low since the mod. Changing the TML sampling line to 18 helped a bit but it's still not getting its own colours right. If I manually change them I can get it perfect (RGB from original Xbox or S-Video from PAL N65)
I've had the suggestion that the G2 might need tweaking up because the mod pulls down the DC bias by -5v. Does this sound right?