For me it's knife cut at 2-3 months of age at branding versus banding at 5-6 months of age 1 1/2 months before shipping to feedlot.
Banding there's greater weight and no lose of gain because of pain from cutting. And no bleeding and death loss as could occur with knife cutting.
More handling hours are needed as a whole if you band versus knife cutting during branding. Banding is unconvenent if you still had the cattle out on range. If you are raising breeding bulls you want to band at that later age to see how they turn out or could turn out.
Banding at 6 months won't effect carcass quality.