Yes thats interesting, I also found myself leaning more towards black CIE era 141/181s than others. I never travelled behind IR/IE livery 141/181s, only super train and CIE black/tan, yet I ignored the 'supertrain' livery models just because I preferred the look of the later IR/IE tippex liveries - strange but true.
The CIE black (&tan with white band) livery 141/181s look great hauling loose coupled goods wagons that I collected to run behind GWR/LMS steam locos before MM era.