I have two road bikes I use for brevets, gran fondos and training ...
I have a 2011 Raleigh Record Ace with a 50/34 compact and 11-32 cassette. I use it mostly for training, and flatter long rides, sometimes. I have used it on rides with 4000' of climbing, but regretted it ... after 100 miles I found i wanted my other bike.
My main bike is a 2010 Lynsky R300 which I built up myself. I use an Ultegra triple 52/39/30, with an 11-32 cassette. On flatter rides I rarely go off the middle chain ring. On hillier rides I've done with 5000' or more of climbing, I use the 30 chainring all the time. I start climbing early on with the small chainring, so that when I get beyond 100 miles my legs are still willing to roll over the pedals.
I have always been MUCH happier on a bike with gears I don't use, but can if I need them, than riding all day and not having an extra gear when needed.
Although the triple might give you some redundant gear combinations, the high and low gears you will be able to obtain will give the widest possible range.