Replace 1 bushing, or everything?

I used poly bushings for everything but the LCA , seems everything I've read says to stick with MOOG LCA bushings , as for the rest of the bushings ride is great with the poly bushings so far , just hope they last , rubber ones were shot and they were in there for 6 years , way deformed and worn through in other spots , 6 years 17,000 miles .
Swaybar bushings 73+ are different , I like the design better than the old system