[quote name='discreet' timestamp='1333965585' post='1608718']There was a thread on TalkBass stating that if you go for FMs you may have to adjust your truss rod, but I can't confirm that.
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You should tweak your truss rod whether you change to a set of higher or lower tension strings if you want your bass playing at its best.
Surprised nobody had mentioned TI (Thomastik Infeld) Flats! My favourite strings on a P by far, got some LaBellas on there right now but planning on switching back at some point.