I am using the 26.0mm / 40cm bull horn handlebars (silver) on my 1970's vintage 531 steel track bike. The bike is fixed gear of course. I want to ride more safely, legally, longer, faster and comfortably on the roads in my area, using an emergency brake. The bull horn bars are working great accomplishing these goals.
I fitted the bull horn handlebars to a 3ttt 25.4mm stem. I only needed to spread the 3ttt clamp slightly to fit the bars. I am using a Dia-Compe BRS 101 front brake (fork mounted) matched to a Dia-Compe handlebar-end brake lever.
When I want to configure for straight fixed gear track use I only need to switch back to the original Cinelli track stem and drop bars. I will not need to un-wrap handlebar tape from the brake lever, cable housing/cable and remove those parts; as I have been doing.
For fixed gear, with a safety brake, when using the drop handlebars. I was using a campy handlebar-end gear shifter as a brake lever (it only worked ok and wasn't very elegant). Plus; for me the track drop bars are not very comfortable on a longer road ride.
The bike set up with bull horn bars is giving me a very comfortable ride, similar to riding a road bike on top of the drop bars & brake lever hoods. Plus my upper body is lower and I suppose more "aerodynamic". The bars work great when cranking out of the saddle. Perfect for longer and faster rides on a fixed gear bike.
The price of these bars has resulted in a very inexpensive solution for this bike. The bike is a blast to ride on the road, and with these bars it is more comfortable for much longer ride.