I don't know if this is phat

but there is no need to go fat. I'm running a Dunlop Winter Tread Run Flat in 175/60-16. It's my first darkside experience - and I was very leery - but I have experienced none of the negatives I've read about CTs. I'd bet that, without prior knowledge, a darkside skeptic could ride it and never know something is different. The only time I've felt the rear "hunt" for its line was on a road so irregular that any tire would have had some personality. It has almost 7,000 miles on it and looks almost new. Nice, after getting 7,000 out of the OEM Bridgestone. 1-up and cruising, 2-up and loaded, city, country, interstate, TX hill country, CO rockies on the way to and from InZane IX, it's unbelievable.
Another option that people seem to like is the Continental Vanco in 195/60-16, but 1) it appears that tire has been discontinued, and 2) it rubs the swingarm for the first 1,000 mile, or so.