I am not a fan of this product. I bought it because it claimed to have a comprehensive synth sample library. The acoustic sounds are quite okay, though not too real sounding for my ears (I know it's a matter of taste).
For the price it actually is a good entry into the "software-workstation" market. I covers all the basics and has much to work with.
But first things first:
The GUI is usable, but could be a lot easier to use, esp. for tweaking the sounds. Everything's too small for me, and switching between the synth parameters too unclear. Yes, usable, but much room for improvement.
The sound of the sampletank engine is basically good, the FX are indeed very good, and it's multitimbral, which I like. But the sample content is only average to my ears, especially the praised synth patches. They sound weak, thin, and all sound largely similar to my ears. Too little variety, and what's there is too thin. Again, a matter of taste, but I don't use SS2 anymore since I bought "Ultra Focus" which has all the solidity and quality and richness I need. The acoustic sounds, the keyboards and guitars, are quite good, and I use them often. Not the drums though, good hihats but the rest sounds like toy-drums. Strings are okay, but the rest of the orchestral stuff isn't great.
Presets could be better and more varied (in the synth department), again the acoustic presets are okay. I have tried customer support only once, but that was okay, even though it took almost 2 weeks to answer an email. But then they helped.
It did crash on me twice so far, but that's okay I guess.
Documentation is okay.
As you can see so far, a quite "okay" software, but I am not too thrilled about it. I replaced every sound category with better ROMplers, because overall, Sonik Synth 2 just sounds too artificial.
I bought it second-hand, and for that the overall value is okay, but I wouldn't buy it new. And I hardly used it anymore, so it's kind of disappointing to me.