I have noticed the ' coffee tone ' in my 8mm Radian , but that dissapares soon after using it , then its real strengths come into play , great eyepiece . The coffee tone does not worry me at all , and I have compared my 8mm Radian with my , 9mm Orthoscopic , 9 and 10mm Vixen Lanthium's and my Baader 9mm ' real' ortho , and they all have their strenght's .
and I love them all .
On the Nagler coffee tone , I have not seen it in mine , I will look for it now , but it must be very slight .
.
Brian .