Scotty Bwrote a review of Shimano Ultegra 6800 STI Shifters on December 1, 2015
Familiarity: I've put it through the wringer
I upgraded from Dura Ace 7900 which I thought was great shifting but Ultegra 6800 is a HUGE improvement. Best word to describe it is smooth. Very light action to shift rear or front derailleur.
Only big adjustment is the trim function. You get 3 clicks to go from big ring to small. First is to "big ring trim", second is to small ring, and third is trim for small ring. This takes a lot of getting used to and is kind of a pain to set up initially. You need an inline cable adjuster to make the Ultegra installation. Once adjusted, it works great!