I have a triple in Ultegra. I am not experienced enough to tell you if it is better than Shimano 105 or not but the guys at the LBS told me it was. I did drop the chain going up hill (and fell ) within the first few weeks of getting the bike last year but made some adjustments and learned to shift better so it doesn't happen anymore. That being said, I dropped the chain twice this week but I've only been out on the bike a few times this spring and I think it needs some adjustment again.

I am not a good climber and live with lots of hills so I still need the triple but I am hoping to graduate to a compact double for my next bike in a year or two.