Ulysses or iaWriter

I’m still vacillating between using iAWriter or Ulysses as my main writing app. I like Ulysses’s interface, but I also like the fact, indeed maybe prefer that iAWriter files are .txt and can be accessed outside of the app. Ulysses seems to allow one to see Dropbox Folders (the complete folder not just individual files) in both Mac & iOS versions, but iAWriter in only the Mac app.