Anyone used one, got one, know anything about them ??

My friend with the skyline saw them at Modified Nationals & had good things to say about them & had been after one for ages. Said it 'ups' the petrol RON by 5 (making Optimax 102 from its original 97) & supposed to be very good for the older original 'leaded' running engines. Wondered if anyone else had experience good or bad?

Info here. Got good reviews..but it's their site & they aren't going to put bad reviews on are they.

http://www.fuelcat.co.uk/mainpage.html