Years ago I had a Beechcraft Sierra with the IO-360 engine in it. It had fuel injection and it always cranked up when it was cold with nary a problem.
Trying the crank it up when it was HOT was a B*TCH !!!!
Several times I actually drained my battery trying to get that engine to start.
It really kills any trust that your passengers have in your flying abilities when you can't get the engine of your aircraft to start!!!
9 to 11 GPH sounds about right for my old IO-360. As it was a non-aspirated engine, I would usually cruise somewhere between 10,000 and 12,000 feet on my long cross countries. Theoretically, you need oxygen to fly above 10,000' but I never had any problems at 12,000' or even slightly higher.