I hit a curb with my S70 and it pulled to the right. Made
appointment at dealer and when I arrived Service Rep tried to talk
me out of alignemnt saying not a common problem (he thought I
was complaining about pulling to the right due to road crown; a
common complaint). In any case, went ahead and did 4 wheel alignement.
It is all done using assistance of a computer which measures and prints
out the readings. There is a before and after measurement taken
and printed. I asked for copies and received them. Looking at the
specs. from the printout (it lists nominal, tolerance and actuals)
my car was out of alignment and the dealer put it back.

There were quite a few measurements (thrust angle, etc.) that I had
never heard of.

We own an 850 and an S70 this is the only time either car has been aligned.

I'd say take the car to a good dealer with the right equipment. Ask to
see the before and after printouts of the measurments. Note that the
computer readouts were time stamped and it took them about 30 minutes
to do the job. Cost was $90 (labor is $130 an hour here).