For what it's worth, I have a familiarity with both Dramatica and K.M. Weiland's Structuring Your Novel/Outlining Your Novel/Character Arcs books (though I wouldn't consider myself an expert on either.)
My own experience (which I think mirrors what others have said here), is that story development models tend to break into two distinct types: what you could call narrative progressions and Dramatica.
Narrative progressions include K.M. Weiland's work, Save The Cat, Hero's Journey (in all its many forms), Jeffrey Schecter's "My Story Can Beat Up Your Story" and a host of others. If you're looking for a roadmap to ensure you get to a novel that hits not just the "beats" but the sense of pace and progression that's found in most commercial fiction, then having a sense of the big moments are that you're building towards can be reassuring.
Dramatica is unique in its approach and I don't think there's anything else out there that works the way it does. The focus, as has been said, is on sources of conflict. Dramatica will lead you to a set of coherent viewpoints on those conflicts and provides a means to go in many different non-traditional directions while still arriving at a satisfying story.
The disadvantage of the narrative progression roadmaps is that, well, you'll learn them very quickly and in a way they stop being useful because the concepts take potentially very complex things (like all the different possible ways in which we might feel as if the story cannot possibly continue, that everything has failed) and toss it into a term like, "Death" or "All Is Lost". Sure, it's still true, but it doesn't cause my brain to generate new and interesting ideas.
You never quite hit the end with Dramatica (or even the end of the beginning, actually, which is what makes it so god-damned hard), so while it is perpetually frustrating, it does give you more avenues to come up with new ideas – your ideas – which is the point of the creative process.
Personally, I've reached the stage where my brain alternates between the two models. Sometimes I need that concreteness of thinking in terms of a set of stages that a book goes through, and sometimes I need to think in terms like "Well, is this really a Situation? Or a Fixed Attitude?" There really are times where you want to think not as if you're trying to reach some conclusion, but rather make sure you've explored all the facets of the sources and points of view on the conflicts in your story. Dramatica has that sense of completeness to its model.
I think it's worth pointing out that K.M. Weiland is in many ways the best of the people out there writing in terms of roadmap models. She's smart, she gives tons and tons of good information away for free all the time, and she goes beyond just structure with some good ideas on character arcs and such. She's given out things like her entire (massive) outline for one of her own novels as well as tons of videos and such. That makes it easier to match the methodology she describes with an example of something that was actually written using it. That's surprisingly hard to find for any other models
I've also found Schecter's book really helpful at points where I just needed to force myself to break out of a spiral of confusion in my writing.
I've also gotten lots of benefit from Dramatica, and several of my published novels were written at least in part using the storyform that the software helped me identify. I've found @jhull a really valuable resource to consult with when trying to both find the storyform and figure out how to apply it. I'm so grateful that I periodically try to drive him insane by posting contrary interpretations of storyforms here (screw you, Jim! Captain America is the MC of Civil War!)
Probably one final thing worth mentioning is that it's not a good idea to blend the two at any one time. In other words, don't try to hybridize a model. Dramatica relies unbelievably heavily on its user community to help make sense of it – there just isn't a book for novelists on Dramatica that's sufficiently user-friendly to wrap your head around it. So if you want to jump into the deep end with Dramatica, just do it. Let go of everything else – and that includes all the habits and thought patterns that have helped you up until now – and let the crazy thing take over for a while. A friend of mine did that – forcing himself to go through literally every part of the Story Guide (which is insane) – and at the end his book changed completely from where it had started and was ten times better.