Looking to replace my front Shock Struts as they are rattling when I go over a speed bump, my R500 with 60K miles doesn't have the airmatic system.

Should I purchase a complete fully assembled strut or just purchase the shock and re-use the original spring?

What brand?

Are the springs on the R500 more heavy duty than the R350 due to the extra weight of the V8 engine?

 

I generally find that the strutt assemblies are lower cost/quality. you cannot find a bilstein complete strut assembly I dont think.