I'm familiar with Joseph's Coat. I don't have it but I've planted it for friends and satisfaction has been good. My personal opinion, I'd look into the Robe introduction. Much potential with either, my taste in roses runs another direction. In some gardens I've seen Joseph's Coat perform incredibly well. Easy to procure and try, it can be amazing.
Edit to add years 3 and beyond have shown more color. Perhaps my luck or planting locations but it hasn't reached potential/goal for me early. Plenty of blooms early on but color variation has taken time (years). I'm not a good rose guy, I consider them expendable. That said I've not replaced Joseph's Coat to date.
