I've been using mine alot lately and I've come to have somewhat of a love/hate relationship with it. More love than hate for the most part, however. Although some of the things I hate are a pretty big deal to me, too, though...
I know NI are playing up the strengths like crazy with all their videos and stuff, so I'm going to first concentrate on the things I don't like about it. Actually most of them have already been stated here already, as well, but here goes my negative list: The MAIN thing that I don't like about Maschine is that, at least in my experience, it does not work well as a plug-in within Live at all. It has already been alluded to here that it lacks MIDI In/Out and therefore you cannot jam out and record your MIDI into Live and then edit and tweak it. Even if you could (MIDI out is 'supposed' to be added in an upcoming update...), Maschine doesn't respond to MIDI in either, so the part you recorded wouldn't be able to drive Maschine anyway. When people started asking about this on the NI forum, they were told things like "just record it to audio" and "if you're using it like that you're missing out on 90% of what Maschine is all about"- that's also part of a whole other story that I will get to, as well... Bottom line, don't expect the kind of integration with Live itself that you are used to from, well, pretty much any other plug-in... Pretty much the only thing you can do is trigger Maschine's scenes via program change, which is pretty much less than ideal for me, personally. Furthermore, when I use Maschine as a plug-in I'm having some serious CPU issues on my MacBook Pro 2.16 Core 2 Duo machine with 3 gigs of RAM. I often cannot use more than 1 group on Maschine even when running only 1 or 2 audio tracks in Live, and even then my CPU meter is close to being maxed out. When I start adding more groups, it invariably sends my CPU over and everything stalls out. It does work fine for me in stand-alone mode in this regard and I can run all 8 groups without any glitch whatsoever. But, I'm an Ableton user, so that doesn't do me a whole lot of good, I need it to work well as a plug-in. Bottom line is that if you also plan to use it mainly as a plug-in, I would wait until (or if...) they get things sorted. Just my opinion, though.
As far as the CPU thing while in plug-in mode, judging from the NI Maschine forum, I am not alone in having these problems, either. Many other users are reporting the same thing, and the thing that really pisses me off about it is that no one from NI or the moderator staff is even acknowledging that there even might be a problem! Blame has been shifted everywhere from motherboards to Live itself... I have NEVER had a problem with CPU using Live on my computer until now and as soon as I take Maschine out of the equation my CPU goes back to normal. Also, the level of participation from anyone at NI over on the Maschine forum is almost nil and quite different from what I have come to expect from the Ableton camp. I would highly recommend for anyone purchasing Maschine to go over there first. Who knows you may think differently about it than I do, either way you will have a better idea...
Another smaller thing is that currently Maschine doesn't have the capability to do Instant Mappings to Drum Racks with its pads like the PadKontrol, Trigger Finger, etc. Since I plan on purchasing the APC 40 to do my scene triggering, my idea was to use Maschine as my drum nerve center by being able to use Maschine's sounds and then jump over to controlling a Drum Rack instantly. I'm pretty sure someone could do this, but it would be nice not to have to fool around with all that, considering that it is a $600 or so piece of gear.... Someone like Machinate or Hoffman 2k could probably whip something like that up over a weekend, though
But, as I said it do like it more than I dislike it. It is fun to use and in stand-alone mode you can certainly do all the stuff shown on the NI videos, etc. The library is fantastic, imho. I like mnml, techno, and house and I think there are some REALLY great artist kits. The browsing is incredible, too. The MIDI control functions are becoming really valuable to me and the fact is that you can do some of the APC-40 stuff right now on the Maschine (APC-40 will eventually do it better, though, I think...) as far as triggering clips w/ visual feedback (although no LED collars for the rotaries on Maschine...). The MIDI side still has alot of untapped potential, too. The FX are pretty good and offer a different way of working, and with a few additions could become a real strength for Maschine (by adding an LFO delay and/or Beatmasher effect from Traktor, etc...). The sequencer is also quite powerful and very fun. However, not to the point that I'd want to give up Live, which almost seems what NI is trying to push people to do, which is a real shame, because in tandem they would be devastating.
In summation, if NI were to fix Maschine's plug-in performance they would have a REAL hit on their hands. Too bad NI aren't making me feel more confident about that happening at this time, though....
But again I ramble. (STFU self!) My 2009 goal was to not post until I put up a track...FAIL!