Technisem a French seed company markets two big ones ... Avenir (average size 19g) and Big Sun (average size 18g). Never seen any data on the average size for the congos but they are huge.
Habaneros are a specific C. chinense variety which are usually always very similar in size and shape.
For largest C. chinenses, the largest I've grown is the Guadaloupe "hab"
Here is a past thread
http://www.thehotpepper.com/topic/11738-largest-heaviest-hab-smackdown/page__p__227952
looking at pictures of growing logs,harvests here, seems congo trinidad end up bigger then the other habaneros. Guadalupe, Cleo's dragon, and Mustard are comparable in size with congos.
I have to agree with Potawie. The Guadeloupe where very large and cool shapes to them too. Congo yellow and red where huge and also the golden habs i grew where quite massive.