I caved and put in an order for the Pirelli winter tires i mentioned earlier in this thread. Unfortunately time was not on my side when i made the decision as most staggered sets were flying off the shelf. I had Dunlop 3D's lined up two weeks ago and htey were gone by the time i went back to make a deposit. I guess ill have a first hand chance to find out the answer to my own question soon enough. FWIW, the guy at the wheel/tire shop said non-rft's can be 30% lighter than RFT, though that's probably exception rathan the norm.
Well, the knowledge i gained here will benefit me down the road should i decide to switch wheels. Thanks all.