I'd like to add a fast comparison between Labella 760FL and GHS 3025 (45-95) on my '71 Precision.
this is a strange bass, that with rounds sounds a bit too "mellow", from steel to nickel, and I was afraid to try flats because I thought it would sound too "dampen" and dark.
I tried a set of Fender 9050L for a couple of days, and they just sounded like rounds with less "grind", so I decided to switch to GHS Precision flat I use on other basses (as mentioned in the last pages of this topic, I "discovered" them only last year, because I was afraid of the negative descriptions they have, as "too dark", "too muddy", until I tried and discovered that they have a powerful fundamental with the most precise projection and "mix center"), preferring the light set (I use them on a JMJ mustang, then two 55-105 sets on a CS1 Precision and Classic 50).
the first impression was so strange, they made the bass overall "brighter", not in terms of high frequencies, but definition and projection: every note was clear and defined, compared to every roundwound set I've used, and they sound livelier.
I've used them for a week, with two rehearsal in two different bands, loving the tone and woodiness, in particular when "finger-slapping" the strings against the frets, making them "bark".
however, I found an offer on a 760FL set of Labella and decided to try them and see how they would have worked on this particular bass. it's a set I know for using them on a Mustang (deep low end, less focused but thick. on the Mustang I preferred the GHS set, woodier and a bit clearer), and I've used the 0760M Jamerson many times on different basses.
despite the defective D string giving me the "mwaaaa" effect (I mailed Labella to see if they can send me a replacement), the overall sound was good, but... deader.
the notes were huge, full of basses, a bit of highs, but lacked the low-mids and clarity. the sound were "softer", and if I can say it, IMHO it's not the sound of "vintage flats" we usually have in mind.
doing researches, and as seen in many Talkbass topics, the stock Fender flats were actually the most used, except for some players like Carol Kaye, known to have switched from the heavy "Medium" Fender (55-105) to Labella (probably a lighter set available, and if I'm not wrong, the 43-104 set was one of them, as used by Jack Casady for a while), and James Jamerson, or the late Donald Dunn.
most bass players didn't change the strings on their basses, and so the stock Fender are mostly recorded in the 60's and 70's, and an example is John Paul Jones, who have used the same set on his Jazz Bass until he started using brighter sounds.
GHS P-flats are the most similar to the original Fender strings, and even the winding material is different from steel flats like Labella: the GHS are "silvery", the other flats are "grey".
here's a picture I found here on Talkbass, I'll add some pictures in the next days comparing Labella and GHS look:
in 20 years of playing I've always searched that sound I used to hear on records and couldn't get the right tone, always something "similar", but when I first tried a set of GHS, I just had an epiphany

it was THAT sound in my head, and now I have them on all my "flatwounded basses", and can't go back to anything else, except for the Pyramid Gold on my three Hofners.
ah! mentioning the Pyramid, which are nickelwound, the GHS look more like the Pyramid/Thomastik than Labella/Fender/D'Addario flats, with the silver colour against the grey.
they also reflect light in a different way.
also, comparing the tension/flexibility, they are the most flexible flats (not considering the Thomastik) I've ever used, even in the 55-105 set. in this specific case, I switched from Fender 9050M (55-105) to GHS 3050R (55-105) on two basses, and I experienced the same exact thing:
the TENSION is a bit higher, but nothing more than 1/8 turn of the truss rod, but they are more FLEXIBLE, they are easier to fret and bend.
same for the 45-60 G and D compared to the Labella 43-60 from the 760FL set: Labella are less flexible, and it's easy to notice out of the package: GHS are easier to coil, Labella are difficult to coil back.
for me, the GHS flats are the best

I really love them, and every time I try other flats, I can't find the same sound and feeling.