ST  X Coil-Over

Great improvement over stock

These coilovers are fantastic! I have put over 20K miles on them throughout all four seasons and couldn't be happier. They ride incredibly well both down low and raised for winter and are easily and quickly adjustable. I would absolutely buy these again and I recommend them and The Tire Rack all the time.

My E39 is daily driven with frequent road trips over 150 miles. I wanted a coilover setup that would go slightly lower than stock M-sport suspension and maintain a comfortable ride on road trips. These coilovers do just that. I have the car lowered such that the fenders are 1/4" above the top of the tire. The ride is stiffer of course, as I was riding on 165k mile stock struts, but very comfortable. I often forget I installed coilovers which is exactly what I was looking for. I believe the ride between brand new struts and the coilovers would be comparable. I really like that these coilovers utilize the stock rubber top hats and strut mounts. I have heard complaints of noise and knocking from coilovers with ball joint type top mounts and wanted to avoid this if possible. The car was designed to have rubber strut mounts so maintaining this helps with comfort and noise. I was concerned about the lack of damping adjustment, but ST got these right on the money. If I had adjustable damping, I would have it right where these coilovers are.

Handling was not much of a concern as the 525i is slow and heavy and I do not typically go on spirited drives with this car. I did take the car for a few drives after installing the coilovers to feel the difference. The car definitely feels tighter around corners and the body roll is reduced a lot, it really feels like a lighter car as opposed to the boat it felt like on stock suspension. However, the steering input is a little worse now than it was on stock suspension, especially while braking, and it is easier to oversteer, but these are likely due to the lessened body roll around turns.

Overall, I would highly recommend these coilovers if you are looking for a sub-$1000 set that are very comfortable and allow excellent adjustability to your liking.