Replacing shocks and struts - choosing parts

I’ve been looking at struts and shocks for my 95 Mustang (base, 3.8l v6). The most commonly available are Monroe sensa-trac and Monroe gas-matic, but no one (including the Monroe website) seems to be able to tell me what the difference is, or why I should prefer one over the other. I’m also having no luck finding out how to tell whether the coil springs are bad, and what the “original ride height” is supposed to be. If the struts/shocks keep the tires in contact with the road, what is the springs’ role? Which has more impact on safe handling, struts/shocks or springs?

Another question: do I actually need a mounting kit? Looks like it has a bushing, new plate and nuts (including the three nuts my repair guide says to not touch), or can I re-use the existing parts as long as they’re in good condition?

Here’s what Monroe says:
"Monroe Sensa-Trac builds upon proven gas pressure shock absorber technology used in the Monroe Gas-Matic design and incorporates the innovative Position Sensitive Damping (PSD) feature which enable the shock absorber to adjust automatically to changing road conditions.

“The PSD design incorporates a unique precision tapered groove machined into the wall of the pressure tube. The groove has been designed and re-tuned for each vehicle. The groove functions as an additional oil bypass around the piston assembly as the piston travels through the grooved area?thereby providing Sensa-Trac with an additional damping zone. This additional zone enables Monroe’s engineers to design Sensa-Trac so it responds as a “double-action” shock absorber that automatically senses and reacts to changing conditions.”

Over the years I have used both with good results. Today I tend to use the Sensatracs. I would also think a good suspension shop could inspect your coil springs and determine correct ride height.

Monroe is a good prodect line, anything will help when its worn out, that vehicle does not even require a spring compressor I think. Check Tire Rack.com for upgraded components also, there may be something there that you want. New springs with struts/shocks can make an old car lively again…

The role of the spring is to control ride height and provide the bounce. The purpose of the shock or strut is to dampen that bounce and prevent the wheel acting like a ping-pong ball.

Unless the springs are broken, eaten up with rust, etc. the shocks or struts have more of an affect on the handling than the springs.

Actually, it’s not a bad idea to change any strut or shock mounts while it’s apart, although I do realize that some of those mounts can be somewhat pricy. As surely as the sun rises each day those parts will fail 2 weeks after changing the struts or shocks if you fail to change the mounts also.
When it comes to automobiles Murphy’s Law is always in the right front seat.