I'm gonna be honest Chris, I don't ever lower my cars. My ep3 is a superb stock ride height.
I don't want the car any lower than it already is.
Why are lowering springs advised?
It's the progressive springs that make the difference. At normal compression the spring rates are similar to stock so you won't notice a difference in ride quality, in fact some people say the car rides better on them. But as you load the spring up the spring rate increases so there's less overall body roll in corners meaning you can plant the car better. This is also why people combine it with the JDM rear anti roll bar as the back end in stock form can be quite snappy if you're not careful.