Kai sounds like he knows his stuff lol.
Thanks for all the help everyone, really appreciate it.

Here's a link that you might also find useful:

http://www.myreptileplanet.com/showthread.php?t=358

I know the guy and he seems to know his stuff.

This part isn't necessarily directed at you, put curious about what others have to say. (I may be opening a can of worms.) As far as trying to tell the difference between guyanas and suris, aren't they basically the same snake?? Yes, they may come from a "different" location, but is that anything other than a man-made line on a map? Both can exhibit varying shades of tail color, etc. One of our Surinam's sides look quite lavender after he sheds, for example. I believe it would be impossible to tell the difference based only on a picture.

To me, it seems to be more of a selling feature than anything else - kind of like calling a Bcc a "True Red Tail" - it's for marketing - it basically tells people that the person selling the animal is aware of how much confusion there is on the topic. and has gone to using this term for the Bcc. 
Bci are "Common Boas"  (they aren't really "Red-Tailed boas" ) - but "common" doesn't sound very "appealing" - and sometimes "constrictor" is left off, too, because the general public relates that word with a BIG, scary snake.

Basically, it comes down to trusting who you are buying your snake from. If you get a snake and don't know if it's a Bci or a Bcc, I would think you probably have to assume it's a Bci (or cross). Although sometimes determining from a pic can be easy, it's not always possible.

Here's another link:
http://reptileguides.herpcenter.com/showthread.php?t=150