Originally Posted by chasm54

If you need low gears a triple is much the better solution, in my opinion. You can get the range with a compact plus a big cassette, of course, but the price you pay is big steps between the gears. The triple allows you to have the range and retain nice tight ratios, which makes for a much more pleasing and, to a degree, more efficient riding experience.

Plus, with the typical 50/39/30 triple you'll find yourself using the 50/39 rings most of the time, and that's a nicer combination on flatter terrain than is a 50/34 compact. You can always go lower than 30 for the granny ring, too, if you need to.