I commute upright on the north style bars now, just over 3 miles. The better I get at biking, the more I find myself wanting to lean forward to get up those hills; my next bike will have drops. But I'll never get rid of my upright beater. And the flat bar bikes I've test driven did NOT work for me at all, my poor wrists.

I guess the best option is to have one of everything! It's not like the bars aren't easy to switch out anyway. Do you already have a bike? Are you new to biking? There's nothing wrong with upright commuting, and I think it might be easier if you're new to it (I know I had a lot of core strength building to do). I'll also mention I always thought drop bars were super uncomfortable until I was fitted and got to try some that were the proper size for me.