I went from a triple 52/42/30 to a 50/34. Where I live there's tons of steep hills, and I didn't want to loose that bail-out gear, so I bought a 11-28. After a few slogs up some 20% hills, I decided the 28 wasn't enough, so I bought a 11-30 and made a custom cassette with the 30 as the bail gear: 11, 14, 16, 18, 20, 23, 26, 30. Most of my climbing is with the 23, but the 26 and 30 do come in handy from time to time. I like the compact and wide gearing in the back over the triple. With this combo I have all the usable gears that I had with the triple. Less shifting. It get's to the point.