Simple question - Go with Bilstein B4 or B6's

[Chboro]

I've read some of the threads pertaining to struts and really can't decide yet. I have a 2001 Boxster S and need front struts. Not looking for anything special and just want the original ride stiffness.

Front reading the threads on this subject it appears the B4's are the stock ride for an S Boxster. If I went with B6's what exactly would change? Can I still use the existing springs? Ride height wouldn't change would it? So, bear with me, haven't done this before and just want to make sure I order the correct struts.