If it’s the same manufacturer as the ST kit I have on my car (You would assume so) then I can definitely vouch for the quality, they’ve been great.
As I understand it the inserts/dampers are the same as those in the KW suspension kits only the ST stuff doesn’t have stainless struts/housings and is the cheaper choice but will still deliver very good KW comparable performance.
However, I’ve not experienced being in a car with the ST sport kit you mention so probably can’t comment any further on that. Hopefully someone else will be along to comment shortly.
Kennedy.