I tried the demo, I enjoyed the FETPress and OptoPress modules on guitars and bass. The free Phuzz module, that boasts 7 individual multi-band saturation settings, is a no-brainer, it could easily be a paid plugin. There's also a free gate, filter, EQ and compressor.
The preamps sound fantastic, to my aging ears, at least. I ended up getting the White Pre during the recent sale. The OMPre also sounded rather good, the others also had their own unique flavours, the analog vibe is great, low CPU, too.
I tend to only use the TCS platform at the moment. My only gripe is the interface, don't get me wrong, it serves it's purpose.
I would like a scalable interface, but that's just me. I also tend to prefer simpler interfaces, I can find too many options overbearing. I use the simpler single TCS option.
A demo, or the free modules, are definitely worth a try.
I felt they deserved a review, hence me writing this.