I use a bass tuned DGCF and another tuned C#F#BE in my recently reunited heavy band. Heavier strings with hex cores are the what I used to use.I will take the blame on that. With goneplaid's statement about tuning, my mind leapt to those subsonic strings.
I think if you were to install them, you definitely would have to file your nut (ahem) with a 175 F#.
Is that bird tuned DGCF? I have had thoughts about adding a bass with that tuning. Sort of a middle point between all the EADG basses and the BEAD bass.
Last session, I tuned down my VP to DGCF. It has medium Cobalt flats on it (45-105?) That worked ok playing with band, but when I tried it again at home, it was too floppy. Time to research strings again!

