H&R/ KONI (rear externally adjustable compression style shock) Well that kit is essentially a set of Konis with H&R sport springs which is exactly the setup I had on one of my TIs for quite some time. The drop is fairly moderate and the ride comfort varies (depending on road on conditions). I would stay this would be ideal for a dual purpose track/street car. The adjustability allows you fairly good amount of stiffness for the track but also allows you to drive the car across the country with a fairly comfortable ride.
Here are some pics of the kit:
Note that the red car has 255/40/17 tire all round and the black car has 245/40/17 rear and 225 front. The lower profile tires (black car) certainly gives the vehicle a different stance.
My sig picture is the same H&R/Koni setup (full stiff) at the autoX no sway bar in the rear and a huge 28mm swaybar up front.
If you like the ride height I would only suggest upgrading to 94-02 mustang rear shocks. They are externally adjustable from the top (no need to unbolt and compress the rears to adjust) and they are a bit stiffer.
Manufacturer Part #: 8041-1186SPORT
You will need a 12mm rear shock mount which TC Kline offers or bimmerworld (I have the bimmerworld ones)
H&R Bilstein sports I had this setup on my wife's 318ti (my current daily driver) and it's awesome on the street. Very composed and great on the highway; well dampened (less jarring when compared the Konis on the softest settings). If the ride height was a bit higher (maybe 3/4 of a inch) it would be perfect for the street and occasional spirited driving. It was also very predictable on the track but a bit softer when compared to the Konis.
Tires are 225/50/16