I installed 7/8" x 34" flat ttrack bars. Very similar to oem bars except black and no crossbar. Bar end mirrors are 3" round universal type ~ $20 from china. Used precision razor to cut off grip ends, used dremel to open end of plastic throttle tube. Mirrors are friction fit - mount by expanding inside bar ends. They've held up well so far and less vibration than stock ones.
That's good to hear, at least. Have you got any pics of it on here? I'll probably go with Renthals (the factory is only 30 miles from here!), and I saw they also fitted those on the Super Hooligan Flat Tracker as well, and looked pretty good. I don't want to take the look and feel too far from the standard bars, as I quite like em!!