For what it might be worth for anyone wondering about which flats to try.
I just got around to trying my first set of Thomastik flats, I think I like them I'm all flatwound and have had my 2 P's and Jazz strung with La Bella's and thought I'd try out the Thomastiks for a change on my jazz and see how they feel and sound.
The good for me is I like the lower tension (think I might be able to dig-in a bit more with these strings) They also sound good (as do the La Bella's), if a bit brite, but they are not broken in yet. The feel of the nickles I'm not 100% sure on yet, the La Bellas are much smoother (slippery). Might be a bit unfair not having really given the T's a chance to break in yet, but I'd guess that some La bellas with the lower tension and same gauge as the T's would be my ideal strings.
Will take the jazz to band practice next week and see how it sounds in the mix.