I mixed up 5 flavors(all with 25% MBV flavors, for strong flavoring) in 60ml quantities, as they were either to be mixed with others(menthol and vanilla custard), or(blu-bacco, blueberry, and 555) because after 5 months, I knew that I liked them.
Also, 25% flavor(100% pg)/75% 24mg nicotine juice(25pg/75vg) got me close(enough) to 50/50 at 18mg that I was satisfied.