For me its drop bars over straight and I have both for different uses on different kinds of bikes. Drops to me are more about hand positions and comfort on the bike. Aerodynamics is always a factor but on a tour bike with the speed, weight and attachments you are never going to be all that aero. Like jolly_ross mentioned I like my touring bike set up with more of French fit (larger frame) a shorter stem with some rise. Just the opposite of what one may want on an aero setup road bike with drops. My drops are not saddle height but more like the saddle height splits the hoods and the drops, give or take an inch depending on how I’m feeling. On my touring bike I have an adjustable angle quill type threaded stem. It is nice to be able to alter both angle and height on the road (mostly height). If I need a more aero position for a downhill it’s natural to slide back in the saddle anyway putting more weight on the back tire and then bending arms extending the hands up into the hooks more and you can get pretty aero with the bars higher. I ride similar into the wind but not as far back on the saddle. If your balance is good fore and aft on the bike there is no reason to straight arm the bars. This lower position on the drops is where I feel most in control of the bike and where I’m best braced for hard stopping. I try and stay in the drops about half the time I would say, but most of the time touring doesn’t require that need for total control I’m just pushing along at a slow pace taking in the views and the hoods are the place to do that.

If I had one concern about drop bars and STI shifting and braking it is my hands are not huge and they are designed to be operated from both positions and I could never get comfortable when the STI’s were placed at the classic location feeling comfortable working them from ether hand position. There are other drop bars that address this and I played around a lot moving them up and down figuring out what compromise worked best for me.

Another difference for me between using drops on a tour bike and a road bike for me is how I would wrap them. On my tour bike I spent a lot of time positioning padding points under the finish tape. Also working around all the gadgets you may likely be attaching to the bars you wouldn’t Fred up your road bike with. I used old bar tape for most of a summer wrapping and unwrapping as I changed things until I got it right. Even with smaller hands I found on my tour bike I liked a fatter grip than I would get with just tape over the bar. It’s all about comfort IMHO.

PS; Just as a side note I’m an older rider that grew up as a kid riding single speed Schwinn bikes in the 60’s and when the 10 speed invasion came along in the late 60’s early 70’s I loved the idea of the gearing and hated everything else about those bikes but mostly the drop bars. It wasn’t until many years later I figured out drop bars don’t have to be a torture device. Those old saddles were bad too.