Yes, you can use them together. They blend perfectly imo (just tried it out
).
1. Sound. You will not get the same sound if you record the sections seperatly.
2. The idea of BBO: Quick and instant. Just load the section and play. No need orchestrate everything in score during your creative process.
3. Cost. It's a BBO installment, and we try to keep each installment below 100€. You get libraries without compromises in quality for just ~ €65 (after intro: ~ € 95).
It's not primarly designed as sketching tool, nor as orchestration tool for the notation first approach imo.
You can use these libraries for these use-cases, but the main strengths are the sound and work-speed to achieve good sounding music.
But you can also use them to thicken up or complement the sound of your other libraries, be it Synchron, SYNCHRON-ized, VI or libraries from our colleagues.
And then there are the BBO installments with sounds and effects you will not get in any other libraries.
We try to design our libraries to complement each other, so you get something new and useful, even if it is a new string library