Assuming you are pitching the appropriate amount of yeast, starting off cooler is generally better. "Getting the yeast going" at warmer temps also generates more esters and, especially, fusels. Most fusels are generated in the first 48 hours of fermentation, and fusels are generally unwanted (they cause head retention problems and head aches and "hot" alcohol flavors).
That said, 72 is not in a big danger area for fusels, though you would not want it to be higher than this. But, for the best beer, IME you are better off starting most ale yeasts in the mid to low 60s.