Tri color breeding

[Purple Mountain Rabbitry]

I'm curious. My friend has a Tricolor mini rex. A lady she met has told her it would be fine to breed her tri to a red or black is this true?

 

[Liddellsbunbuns]

Red would be best b/c the ej gene is dominate (sorry for spelling errors) over the red's e. With black you would end up with castors probably with slight harli markings unless the black carries the ej or e gene.