@Ryan I didn’t option the HK and honestly if you haven’t had upgraded speakers on a previous car then the HiFi speakers are pretty good, there’s 10 speakers including 2 under the front seats, the vocals are crisp.
The down side is the bass if you want to compare the two, it isn’t going to be as exaggerated as HK can be and the volume is slightly limited, where HK can be extremely loud at the maximum level, I’ve heard it before it’s deafening. Tbf I used to have the base speakers on the 1 series and this is definitely an upgrade, maybe the iconic sounds the car makes would be more of a surround sound/slightly louder but generally I’m happy with the HiFi.