Without a doubt, the wing color in both varieties is problematic. There isn't a Columbian or Buff Columbian Cochin in existence with perfect wings. The reason I say this is that, when I've gotten close to having decent wing pattern, inevitably the males are overmarked in the saddle and the females will have smutty cushions. Additionally, for whatever reason, these two varieties have issues with weak wings with a tendency to be split although they will have the axial feather. Males tend to be too long in the wing feathers which drives the poor wings across the board. I am finally producing some fairly clear cushioned females, and of the group of pullets that I raised this year, I kept 2. I'll try to get a photo of the one (better type and color) and post later. When I first got into the Columbians the males trended toward being very brassy no matter how much or little sun they were exposed to. I still get brassy ckls but not near as many, so there is still some genetic issues with red in the background. However, that helped me in the Buff Columbian department I think. I started the Buff Columbians a couple years ago with only 2 females and no males. I used a Buff male across the Buff Columbian females to produce a couple cockerels that carried 50% of the pattern genetics. I then crossed the best of those to a regular Columbian and produced some fairly nice Buff Columbian pullets. All ckls from that cross were discarded since they were nothing more than brassy Columbians. I've done some backcrossing and also picked up an outside BC male 2 breedings ago that seemed to help out in the pattern department. So to answer your question, I find the pattern/color of both to be equally challenging. You are dealing with not only pattern, but different undercolor vs surface color. I would say that of my patterned varieties the Columbian and Buff Columbian are probably the best typed birds. I have a couple Columbian hens that are as good typed birds as the Blacks. They just wont' get a second look in a show because the wings are junk. All is not lost though, as the wing structure and pattern is getting a bit better each year. I'd say in 3 or 4 years the wings will be better for color and not as loose.