I often wonder how these lowered cars don't get chased off the road under safety rules (Construction & Use). In the main they are basically unsafe due to the lack of suspension travel and consequent loss of road-holding on the ordinary bumpy UK roads and gain nothing from this lowering. In the main they look very odd too.
However, if the desire is to reduce the road-holding and road performance for some reason or other, then be sure you reduce the loss of safety as much as possible.