RTB advice

I have been doing a good amount of research on Red Tails and they seem to be the most docile of the larger snakes and don't tend to get over 8 feet. Also they seem to be about the same as a ball python to take care of just bigger. Is this true or no? If not what is the most docile big snake? I keep hearing about these BCC's or BCI's....what does that stand for?
I would be keeping the RTB in a 20 gallon for the first year then making my own cage for it after that. (4x2x2 is what they need as adults)
Any help is appreciated and any sites that you know of for info you can post it here. I was going to RedTailBoa.com but I can't get used to the way the forum is set up and can't find nothing.

Ok well I got the whole BCC vs BCI thing now. haha
Looks like I want a Peruvian Red Tail. They aren't the brown color as most BCC's but rather have a yellow to them. But I see as baby's most are the gray color. Is this common? Also do breeders actually sell Peruvian's and what would it cost me if so?

Bump for the OP

Whether the animal is docile usually varys from animal to animal, but boas are typically known for fitting in that category. BCC's will get over 8 feet, they are significantly bigger than the BCI's. Males of both types are significantly smaller than the females. Most boas are beautifully grey as babies, then most go brown over the first year or so. Some BCC lines keep this grey more consistently. Silverback bolivian boas and cay caulkers retian grey too, but they are both rarer to find.

+1 for a Peruvian BCC. They are so incredible, definitely on my wish list.. so pretty, so big!

If what you're looking for is a big snake that doesn't get to "giant" sizes and has a good chance of being a great pet for handling, RTBs are a great way to go.