changing out front springs on 240?

Last week I had to replace the front struts on my 1992 240. Also, the left ball joint was worn and replaced. It rides so much better. The car has 236,000 miles on it. And I know the struts were very worn and the springs probably had to work overtime for about a year. My question is : should I go ahead and change out the front springs? Is there any rule of thumb for a car with this much mileage? The replacement struts are Boge gas..and seem to work well. Thanks for your input. JB remove parenthesis to reply directly