Though I understand people choosing to only use a primary, the only potential issue I see in using a secondary is easily mitigated, infection. Assuming normal care with sanitation, you should have no problems using two stages.
I don't buy that secondaries are less efficient at reducing off flavors than a single stage setup. There should be plenty of yeast still suspended after 1-2 weeks in the primary with most yeast strains. Most (if not all)commercial breweries I have seen used two stages.
I have brewed roughly 50 brews in the past year plus since I began brewing and have not had a bad beer yet. True, my taste buds may not be as refined as some, but I also give samples to numerous experienced brewers that do not complain about off flavors. I have certainly had bottles that were off, but with a little extra bottle conditioning, all have self corrected, some quicker than others.
Bottom line are either option is more than viable, personal choice/preference.
Just my 2 cents...