Pyramid flats on my short, medium, and long scale Series I instruments have all had an excellent tone but if you can afford them, I most like the tone of TI flats which last forever. I also like them because they sound just as good when playing with a pick/plectrum as one’s fingers and I don’t need to bring two basses with me for sponges we play where I use a pick. But then, I’d consider myself a traditional bassist (no snap, crackle, pop here other than in my breakfast cereal) and think most rounds on Series basses have teoo much treble. Some players though are going to tell you the tone of TI flats is too dull for their tastes. Beware that, TI flats have quite low tension that some people don’t like/ can’t get used to. I have also not been able to get a pair that work well with a five string non Alembic semi hollow body bass I have because even long scale TI strings don’t fit it. The extra long TIs were like spaghetti noodles - the cooked version that is.