Which Bilstein Struts...Heavy Duty or Sport?

[michael_dba]

I'm considering changing my struts since the car has 68k miles, and I don't know the previous history of the car. I've seen replacemnt shocks at sources like Pelican but noticed that there are two Bilstein options. Curious if anyone here can tell me the differnece between the two types. For example, which one is firmer or softer? And are these OE replacments? I drove a stock '99 Boxster that seemed to have a smoother ride...or I should say it seemed to have better dampening, and was a little less jarring over rough bumps....I have Yoko ES100's, and the '99 had Bridgestone Potenza 750's on it....could be the reason too?

Any input would be great.
Thanks,
~Michael