for me this is:
without a shadow of a doubt.
_full daw that is the only one to play in that range.
_got a session equivalent wich is a matrix grid of patch that can be trigged as 'scenes' as well, and reced to arrange/sequencer.
_Patchs can be anything, with unlimited sub-patchs levels. from grain sampler, vstis, step sequencers, whatever.
_if you want something specific, you just build it in no time/limitations.
_work natively as stand-alone, or VSTI inside any daw.
_Any patch you make can now be exported as stand alone app, vst or Vsti to re-use in other daw, distribuate or sell.
_Full custom build of user interfaces, make shorcuts to what you really needs using knobs, sliders, arrays, 2D matrixs, XY ect..
_build custom midi controllers or bomes like translations with no equivalent.
_Modularity pushed beyond imagination limits, anything got I/O that can receive/emit data (ie lfos for anything, quantized trigz..)
_Out of the box gamepads, wiimote, kinnekt, any HID and video mocap as controllers.
_Out of the box Multitouch and gestures for all gui modules.
_powerfull scripting language and Internal wireless language if impressive list of basic primitives modules weren't enough.
_instant recall and morphing of any sets of parameters, including VSTs via powerfull preset manager
_ability to dynamically alter routings, even dynamically load/unload of vsts/patchs.
_full surround suport up to 32 outs.
_full OSC support.
_fully free functionnal version.
_ridiculous price for what you get (119e for unlimited pro, and a special promo @59e now!!! find something equivalent at this price!!! you won't even find something that got 20 percent of usine possibilities.
_The creator, a french guy called Olivier Sens is a great musician, and awesome intelligent and fast programmer. He really listen to users request and i would say 70 percent of requests end-up implemented in a better way you would have thought yourself.
He for long used Lemur,Max-Msp,and reaktor and was so bored of limitations he started to build his own stuff over 10 years, that summ-up a bit the thing...
have a look at free version, it's just free and let you see the potential of the beast. of course at start it seems a bit complex, but really it's not. but don't espect a noob interface a la ableton.. just build your own vision of your dream setup.