Today I headed out east to the beach house to mow the lawn. Once I had finished, I thought that I would take Benzie out for a drive. Driving along, I realized that the front end was behaving like it had before I replaced the subframe bushings. When I arrived back home I took a look at the (front) left rear bushing. Sure enough, after only eight months, or so after installing new aftermarket bushings, they collapsed. I'll be ordering a new set from my MB dealer tomorrow. Le$$on learned.