All my bikes have triples. With the hills around here I can't imagine not. Actually I don't have to imagine, I bought a used Trek 400 with 53/42 f and a 12/25 r and basically was getting off and pushing way too often. I switched the smaller chainring to a 38 and the rear to a mega range freewheel with a 34 tooth big cog. I had to change the rear derailler to support this range of gearing also. This change helped a lot, but once I got my Axis with a low gear of 26 f x 32 r I sold the Trek.
If you are going to change gears you may want to determine the ratings of your deraillers, both the max cog and range of the rear derailler.