I switched over to Bitwig back when v2 came out. I was thoroughly impressed (and still am) at the modulators, the midi timing and the arranger - splitting entire groups is great for large compositional re-arranging. Compared to Ableton it just worked no matter what I through at it… almost.
Sigh
The UI is just so sluggish on a Mac, it’s painful. Also the bare bones instruments require you to build in functionality. This is great for flexibility but not so great when—for example—you simply want to key track a filter. You pretty much have to build everything to get the functionality that you would expect. I’d prefer some modulators pre-wired. Sure you can make you’re own but who has time for that 
But the worst thing is the audio engine suffers from a huge amount of audio clicks and zero-crossing pops.
Bitwig has a clip mode like Ableton Live but it’s useless for live recording > playback as it glitches at the moment it jumps from recording to playback. Additionally, live triggering different clips midway through their playback will also result in a click. Finally, trimming audio / events in the arranger view suffers from the same problem. Bitwig adds auto-fades at the Audio Event level but not at the Arranger Clip level so you spend way too much time re-adding fades on clips that have been split in the main timeline. There are a few other strange inconsistencies that don’t make sense but they’re hard to describe.
Alas, I recently moved back to Ableton but I I’ll be back if they fix some of these problems as they ultimately kill the flow of the software.
V3 does look very cool though and I’m a fan of their pricing model. I sat out 18 months of updates but can simply jump back in when V3 comes out for a reasonable price, unlike Ableton who charge $300 per major update.