I have the impression Massive X got an undeserved reputation of being cpu heavy by requiring a more recent cpu than most vst’s. This is not for it’s actual use of cpu resources, but for specific requirement of instruction sets.
It’s actually remarkably efficient on cpu usage compared to for example Diva and Repo 5. It’s on par with Sylenth1 and perhaps Serum, but the latter sucks in sound quality (at least to me 
).
Massive X sounds amazing to me, but I suspect a lot of users don’t realize this (anymore), as the difference of improvement has become only noticeable on more high end audio systems. Perhaps to compensate for their lack of audio equipment, some users flee to (discredited) graphical analysis of aliasing, which is a bit disheartening, but perhaps the result of every douch bag that knows how to install a DAW nowadays considering themselves a producer.
That is not to say I think Massive X is a successful product. It’s not. But not because it’s audio engine sucks. That’s not the problem. It’s the gui. To state the obvious, Serum has a much more modern gui (and more and more other VST’s), and really that’s where Massive X has failed.
I think the reason why it fails is perhaps most interesting, and shows where NI really is losing track of their course. Because, and I’m very puzzled by this, but if anything, NI can’t get a basic gui to function properly anymore, anywhere. This seems especially the case when looking into the performance of the gui’s. I have noticed this with older software (for example Maschine, which still renders the gui on the cpu, and very inefficient for some reason). But somehow, incredibly, instead of finally harboring the power of the gpu, Massive X makes the same mistake of inefficient graphics performance, but on the gpu. In fact, this seems to be the second cause of the reputation of Massive X to be ‘cpu’ heavy. When monitoring the resources Massive X uses, it turns out it mostly sucks up gpu resources (especially on retina displays), while cpu usage is nothing above average. Why is a mystery to me, but a recent update that includes a ‘gpu light’ mode hints at some awfully inefficient (and useless) use of gpu rendering: the biggest apparent difference when turning on this mode is the disabling of ‘shadows’ underneath all the knobs and sliders. I’m not sure what kind of shadows they are trying to render, but it appears to be total waste of gpu resources to start with for a 2 dimensional gui of an audio synthesizer.
I’m not a professional graphics programmer, so maybe I’m missing something though, but I suspect, if anything, they need to hire a couple of proper graphics programmers to offload the bullocks that is now thrown into the gpu (and cpu in older software), so their audio engines can truly show their true potential again. But somewhere I suspect there are a couple of managers walking around that say to the developers “we’re an audio company, we don’t need dedicated programmers for graphics, just make it yourself!” Which would perhaps be fine if the developers could decide their own deadlines and take the time to actually learn the skills of the trade while upgrading the gui besides delivering a state of the art audio engine. But for a company of this size, that seems like a very unrealistic approach.
It’s a pity, because they have made some awesome products, and underneath the surface their current products are still filled with awesome features and capabilities if one dives into them. I’d hate to see this all go to waste in a pool of misappropriated venture capitalist money and higher management levels that only look at spreadsheets and don’t know how to care about actual long term product quality, and the people that make and use them.
