I would look at the terms...Hex Core, Taper Core, Exposed Core...
Since I moved to this kind of string, on the B, my basses are tight.
I love the MTD 135x's and the Smith 130's. I have a list of others if you need to explore...
Make sure that your tech sets up the bass with the taper core string(s) in place otherwise you will be hating life ... bad intonation
good luck ... you will not be sorry.