it's difficult to quantify the differences because it can be a 'felt' issue with one's
butt. however, I will try. folks often have competing desires for lowering their
ride and then struggle with comfort, ride ability, handling, clearance etc

I have no experience with HR. I first tried Vogtland and felt the ride was too
harsh so I sold them. I also tried cutting one full coil off and felt that was too
harsh. I ended up with Eibach and they (to me) had a good balance between
firmness vs comfort and handling.

I paired the Eibach's first with Koni yellow body (3-settings) shocks but the
firmest setting was too soft to control the body rolling when pushed into fast
sweepers (e.g. freeway off ramp).

I settled for the Bilstein HD, then Sport for my w210 RWD, both of which shared
the same dampening rates but the Sport was an inch shorter. The valving
characteristics were clearly firmer than the Konis and I liked the balance of
the Eibach/Bilstein and stayed with them.

The final result was very little body roll and about 1.5" lower on #2 pads...
while still retaining a firm and acceptable comfort on the freeway. Driven on
poor roads and transiting over railroad crossings, you are reminded you have
firmly dampened shocks as the vibration passes through your car seat, to your
butt, and up your spine (though not painfully so).

When the car is fully loaded with passengers, the added weight of roughly
1000 lbs reveal the limits of a lowered ride. Care must be taken when switching
from level pavement to steep inclines. As such, I rarely load up with more
than 3 and will reach for the keys of a different family car. The 210 is my
guilty pleasure ride and my only auto transmission vehicle.

anyway, anecdotal from one owner

__________________
-- raymond~
47º 34'N 122º 18'W