Well it really doesn't serve a purpose other than you are too lazy to physically go and adjust your suspension yourself.
Like I said, in some cars, you can get to the rear shocks to adjust so this would be a good alternative (i.e celica's).
Anyone with koni's know that they usually have 2 settings they use (street and if you are tracking the car). There isn't much adjustment in between or on a daily basis. Anyone with the money to blow will get better revalved konis which are even better.
You could also get these:
Thats bling and functionality in one piece.