The Slipstream doesn't really look bad on the Ford Lynx RS. But main reason for using it would be functional. It's a lot lighter than most wheels out there. Problem is it's hard to find one that would fit the RS in terms of offset.
BTW, if you have an RS, you may want to register your RS at Ford Club's RS Registry. To date, we already have 33 RS cars/owners listed there. That's exactly 15% of all the RS cars released in the country (only 220 were released).