I owned a small meat market a few years back and learned a lot through our vendors and such. Essentially branded meats "Certified Angus" "Hereford Gold" etc are all just marketing arms of large commercial beef producers. These are to give them a brand so they can sell at higher prices and can segment their distribution. The same producer might sell the same beef under 4-5 labels (1 to walMart at lower prices, 1 to to warehouse stores, another to boutique stores at much higher prices etc). Also, to be called "Angus" or "Hereford" you only have to have a small percentage of that breed. Some well under 50%. The other 50% of the cow can be anything. several breeds in fact. So if you buy an "Angus" steak, it may be 10% angus or 50% angus. The rules are very dodgy and made up by the producers so they can be anything they want.
Your best bet is to shop by how it looks and leave the branding to the experts. Flavor difference in beef comes from how they are finished (corn, grain, grass etc) not their breed. I've also bought tons of choice steaks that were better looking than the prime sitting next to it so knowing what to look for is key.
Just find you a very well marbled cut of beef that has a great color to it. Some are brighter than other but there are many reasons for that. I actually like a darker steak (not browning, but dark throughout). That shows it's been nicely wet aged in the cryo for a few weeks and add flavor and tenderness. Bright red in grocery stores is fine but it's normally been in a case that has pumped full of carbon monoxide to keep it red. Yeah, the poison gas. it's in harmless amounts but I prefer to go without when I can.
If you like your butcher and he has been hooking you up with the good stuff, I say stick with him. Him calling it by a brand is a way for him to be able to compete against all the monster food warehouses so it's a good thing. It will cost you a little more but consider that the cost of having a good butcher. It's worth it..