I don't think you are going to get any type of consensus on this at all. There isn’t even any agreement on what air pressure to run in these tires among the people that are riding on them. People have been running Toyo’s, Dunlops, Goodyears, Falkens, Kumhos, Coopers, etc. Some go with all-weather tires, some with winter tires and some with summer tires. You can find people who have run just about every type of car tire there is. It is really all over the place. Some have expressed a preference for run flat tires and some don’t. There are more opinions on this subject than just about anything I can think of. Believe me, a lot of those opinions are not restricted by any knowledge of the subject either. Watch out for good intentions disguised as facts.
My advice to you is to read all you can about this subject. When possible, find out how many miles the person has ridden on a car tire before sharing their opinion. Personally, I give more credence to those with higher mileages. You can find a lot of “it’s the Greatest!” opinions with only a couple of hundred miles under their belt. Those folks are still intoxicated by the newness of the experience. Do a Google search for “car tires on a gold wing” or “car tires on a motorcycle” or “Darkside”. Check out totallypissedoff.com, gwrraokla.org/_wsn/page12.html , Tom Franken’s website, Daniel Meyer’s website, and do a search on this board and the GWRRA tech board and the WOTI (Wings On The Internet) board for references to car tires. Be prepared to spend some real time on this because the one thing you will have to admit with no possibility of an argument is that 'car tires were never designed to be used on motorcycles'. If you still want to go ahead and put a car tire on your bike then do so armed with all the knowledge you can get.
What do I use? I have a Toyo Proxes T1R 195/55R16 on the back of my GL1800. It is not a run flat and I am currently using 28PSI in it for solo riding. I am not recommending or condoning the use of any automobile tire on a motorcycle.