I'm a huge fan of flats. My P-Bass has had the same set of La Bellas on it for 3 years. I had flats on my 5 string Jazz, but put Rotosound rounds on it trying to get mid-rangy punch. But they are just uncomfortable and I get a lot more finger noise and squeaks with the rounds. The Rotosound 77 Jazz Flats sound quite different from the La Bellas (and not just because they are 3 years old
). They are brighter and have more of that snarl the rounds usually have. With the Jazz pickups, I was able to dial in that tone I was wanting. I think I'm going to switch back to the D'Addario flats I had on my 5 string since I have this Jazz now.