1993 960 brake question

Hi

Installed the snow tires today and looked at the aged disk brakes on our
960. Rotors are all original with 155K Kms on them (and 11 years) pads are
the second set, with plenty of meat left on them (done at 110K Kms). The
rotors are getting a nice lip on the top of them - from years of wearing I
guess... there is no warp to them though - brakes very smooth... The rotors
are starting to groove ever so slightly... almost like rippling effect and
there are spots that look like they are being attacked by some kind of
rust - tiny little effect with little holes and discolouration... Maybe
porosity in the metal?

Anyhow, we are thinking we need to change the rotors and pads, at the same
time would you recommend getting all the calipers done? Or do Volvo calipers
tend to hold up very well... We've had one rear caliper changed because of a
leak in the slave cylinder.