+1 for the Mudslinger - this keeps the crud of your legs and the rear schock. If you have got rid of the OEM rear wheel bumber thingy then you could also get a rear mudguard extender which will stop roadspray from flying up onto your back as well.
Tip for anyone looking at a nippys hugger, look at the pic on nippy's site, then look at the 1200gs hugger on skidmarx site. See any difference in the pics? I don't. See any difference in the price? Yes, £20 or so.