Originally Posted by
chasm54
It's true that a compact double with a big cassette will give you a similar range to the triple. But the triple is still the superior option, because you can achieve closer ratios and less shifting between chainrings.
Of course, superior is in the eye of the beholder, but I agree w/ chasm. Take a look at
http://gear-calculator.com/#
it is a very nice tool and you can compare various front/rear gearing choices. I expect that I could tolerate the taller gearing at the low end, but the jumps between gears are very off-putting to me. I like pedaling at 90-95 rpm, and a triple with a 12-27 lets me be at 95, upshift, and be at 89-90. You can use the tool to figure out how to emulate a compact double setup using your triple; try it out on the bike and see how you feel about the 12% jumps. Clearly they don't bother a lot of folks but I really dislike them. Sadly, that means that 105 is the top-end groupset for me, Ultegra and Dura ace don't even offer triples any more.