for what vehicle? can you get away with replacing just the bushing, or do you have to replace the entire arm? if the entire arm it would be expensive to buy, not so expensive to replace, but if it's the bushing it would be the opposite... cheap to buy bushing, but having to use a press to push out the old one and put in the new one is not as fun. small-time mechanics may not have a press and would have to send it out to another shop