I've got sax suspension on my D22 and after getting 4 different sets of springs off them, I am still not happy with them, they are crap. If I was you I wouldn't be handing over any money to them until you are happy with the results, once they have your money that's it. That was my experience...
See Sax have been members for a while now and log on regularly but won't even comment on how to fix our problems. Real good customer service.
Worst mod i have done to my nav, biggest waste of money ever, it really SUX.