I have found some 1911's - or maybe 1911 magazines? - function better with one less than the max capacity. Also, with some rounds - notably .460 Rowland and 10mm - if a round is chambered and not fired, it needs to be checked for possible bullet setback, which can cause dangerous over pressure. Since I hate to discard "good" ammo, I prefer not to chamber a round unless I intend to fire it. BUT - that said, if I were carrying for protection, and serious about it, and using a firearm that can be carried with a round chambered SAFELY, then yes, I would not hesitate to carry with a round loaded, but still probably one less than the maximum capacity. I have Wilson 10 round mags for my .45 1911's, by the way, as "reloads" or bedside loads, and many extra magazines..
