I only use the Fender NPS (7250s medium) strings on my Jazz. Hands down the best string I have used on this bass.
I like the Fender flats as well, so maybe I'm biased.
As for life span, the set on the Jazz now were on my P bass new when i bought it. Put flats on the P and the rounds on the Jazz. That was in October, used the J bass out 3x in addition to light practice. Think they actually sound better now than new. Still have that sizzle and clean "ping or ring" if you will, but will also generate a real nice low end.
The fret buzz seemed to fade a bit after a week. Used them out the first time of hard play, then set the truss rod and action again. Hard to tell if it was all wear in or weather since I live in a real dry climate. Barely notice any fret noise with them after 2 months of use.
Keep us posted.
Jazz #1200 / Precision #1131/ Colorado #327/ Fender Rumble #327
Last edited by mrb327 : 12-26-2013 at 06:35 AM.