Depends on the suspension geometry, the bushings on my 740 are shot and the
car tows dangerously to one side under hard braking and pushes to the other
side under hard acceleration, definitly something I need to fix soon. On
other cars it'll just make clunking sounds and can cause tires to wear
unevenly. Either way you'll want to replace them eventually, though $800
sounds like an awful lot of money for the job.

If these are the bushings I'm thinking they are, they're over $200!
each, and are a real pain to change.  The rear suspension can move out
of alignment several degrees when these are bad, and as a result you'll
get some random rear wheel steering (unsafe) and it'll eat rear tires.
So you pretty well need to do this ASAP.