The Brush birds are correct to standard in almost all respects including weights. I have seen some birds out of Cubakids stock and from Zook/Brush crosses that are also correct in all respects, save the hackle color. I would say the BB Reds are and always have been the "main" color in the breed, and are by far the best in terms of type, especially tails. Yes, a lot of BB Reds tend to come in a little undersized, but good sized ones are out there. The blue reds, golden and silver duckwings, blue goldens, etc, all tend to come in the smallest out of all the color variants.They also seem the worst for blue legs and white earlobes. I think the best examples of the " duckwing variants" can have fantastic tails, extreme elegance, broad backs, and good heads. Good ones are hard to find anymore though. The duckwing variants lay the smallest eggs, and are quite thin. The best BB Reds lay decent sized eggs and can have some bulk to the body, especially if they have Schmudde( Brush) blood. The blacks,blues, whites,pyles, brown reds, spangleds, etc I will lump all together for this discussion. What I have had from these colors have generally had good size, were meatier, laid good sized eggs, and had good temperaments. However, they all throw a lot of off types, and very few have correct lobster tails. I would consider all these to be still works in progress, more years and more breeders needed to perfect some of the details. Yes, there are a few super nice ones of some of the unusual colors out there, but, overall, they need perfected a bit more. The simple explanation is the rare colors are the least inbred, and have been crossed with other breeds more recently than the BB Reds. This gives you better size and vigor, but you pay for it in the increased number of culls.