No (which is very much preferable, IMO); they link you directly into the airline's purchase flow. The search results include a lot of folks who do, like Expedia, if you want the third party experience. It's not much fun when things go wrong.
If I ask the airline to cancel my booking, what happens? Do they do so? Does the Duffel markup come back to me? Do I get status benefits from the airline?
The idea of buying any ticket not directly from the airline terrifies me now.