As an Ableton Live user, I think the best options are Either get both, use t hem for what they are good for, or only get Push. I don't think it would be wise to get Maschine as a primary controller. As a Live controller you just can't compare the 16 pads to 64, and the other functions in Push specific to Live. It's all about the Maschine software being used with it's hardware.
If your'e cool with drum racks, and doing sample editing in the usual mouse fashion, then Push will be perfect. If you want that extra control of drums, one-shot samples and sliced loops from a dedicated controller, then add Maschine.
I have Maschine and I'll be picking up Push. What I'm not sure about yet is how much I'll use Drum Racks for my Drum tracks. The way Push handles them looks impressive to me. The Maschine integration is still lacking to me (exposed automation parameters, the way of linking patterns to clips etc.). It might be nice to simplify a bit and use Drum Racks more with Push. For slicing though I still don't like Live's methods. I'll keep using Maschine or Kontakt.
What can Push do in Live specific that Maschine cannot do? I ask because you probably have more experience with the Live/Maschine combo than I do. I have been doing complete instrumentals in Live using my akai miniak and maschine as my controllers. I do have to use the mouse to open up plug ins with maschine but I would have to do that with Push too. I don't do much automation either. And I don't use the Live devices much at all either. Is there something I missed?
Are you asking from the point of view of using it as a Session View controller? Or as Drum/Instrument controller?
If comparing them as Live controllers, Push can of course browse the Live browser and do other Live specific things (like functions on clips etc.) that Maschine wouldn't be able to do when being used as a Live controller. But it's also about what Push does better, such as the overall mixer control and layout (since Push was made for Live), and the whole melodic instrument control and the larger number of clips etc. Also the drum rack sequencing. Maschine has it's own sequencer but if you want to sequence directly into Live clips, the Maschine won't do that. And that's where the Push advantage is for people who mostly want to use Live's built-in functions. It integrates with it.
But if you're comparing them as sequencing software/hardware, then Maschine has it's own Browser and similar (better in most ways) functionality, internal sequencing atc. but these are only benefits when using Maschine with it's dedicated software, which means you're using it as a device, be it for drums, slicing, sample triggering or whatever. In this regard, there isn't really anything that Push does within Ableton that Maschine can't do in it's own dedicated software. But you can't really compare the units themselves without comparing the software that it supports. Ableton can do many other things that Maschine can't. But that's no reflection on either hardware unit.
I guess my point is that you can't really compare the two units on their own. As an Ableton user deciding between the two hardware units, it comes down to comparing:
1-Live + Push
2-Live + Maschine plug-in + Maschine
3-Live + Push + Maschine plug-in + Maschine
So although I think Maschine is a better Drum Sampler/Sample slicer and you can do a lot more with the hardware in terms of those sampling functions, I'd probably still take Push if I could have only one, because of what it adds to the overall Ableton workflow. So I would chose between 1 and 3 above.
Since I already have Maschine, the thing I'm curious about is; I wonder if I'll just enjoy using Drum Racks with Push rather than Maschine with it's software. Some things that I like the idea of with Push for Drum controller are:
-I like the sequencing steps being available at the same time as the trigger pads. That's cool. An dthe fact that you get 32 at once instead of 16.
-Notes go right into a clip. You don't have to assign a program change or a note value to a pattern like in Maschine and then put in that note/program change in the clip you want to fire that pattern.
-All parameters are automatable in Live directly (in the track and the clip now). Maschine you get the 8 macros per group.
But the things I don't like compared to Maschine:
-Slicing is more messy in Live. You can do a lot less on a single track. But I don't do that much slicing I guess. And there's always group tracks.
-You only get 8 macros for the entire drum rack! At least a Maschine device has 8 groups, each with 8 macros. Maybe a MaxforLive device could be made for the sole purpose of being a big drum rack mixer/parameter mapping device.