I feel like I'm not understanding something when people say it doesn't matter. Maybe I'm just closed minded, but Bitwig is definitely the best. Ableton crashes regularly, making it really hard to finish big files. Also, the interface is weird to navigate and annoying for my workflow (which I think is pretty similar to the majority of workflows). FL's interface is nice, and super convenient, but it doesn't lend itself well to controllers and feels like it's meant to be easy for beginners while still retaining a full set of features, which I consider a negative trait. Also, I never understono the whole 'give automation it's own track' thing.
Bitwig has better plugin effeciency, as well as sandboxing in the rare case that it does crash, so it takes literally one click and 5 seconds to restart a project that crashes. Also, the plugins can be reloaded 1 at a time if they crash. Bitwig's native instruments and effects are enough to make a whole track (then again, so are FL's and Ableton's), and run really smoothly in Bitwig's engine. Speaking of the engine, it compensates for plugin latency, which is kinda unnoticable in most situations, but in the cases it isn't, it's really obvious (I think Ableton might've gotten it recently, but the point is that Bitwig was first). I think the biggest benefit to Bitwig is that it's the most recent. People left Ableton to make Bitwig because they wanted to rebuild it from the ground up, using their previous experience to make a whole new project. Because of this, it''s really easy to fix issues, as well as add new features. Updates come around every month or so, and when there are big bugs, they get fixed in about a day. Bitwig may be the newest big DAW to the scene, but even in the 1.xx versions, it can still compete more or less evenly with the 9.xx and 12.xx versions of other DAWs.
If I got anything wrong, please let me know, I would hate to guide someone to the wrong DAW.