I know this is a really old post, but I thought I would follow up with what I learned. I tested baking hoses and it works quite well, here is what I did to form my own brake booster hoses.
I started by testing a few pieces at 350 degrees for 3 different times with 1/4 od soft copper pipe to hold the shape, the first one I tested with my tire pyrometer to see how hot it was (hotter than 200 degrees in the middle of the rubber and that is the limit of the pyrometer, so I didn't test the others). I decided to go with a 7 minute bake, as you can see all three held their shape, 9 minute stunk a bit more so I went with the middle of the 3 for my final bake.
I used 3/8" fuel injector hose which fit perfect, and has thicker walls than some of the other vacuum/fuel line hoses. For the real hoses I greased the copper tube so it would be easy to get out. I baked at 350 for 7 minutes, and the hoses stayed quite nice, not quite as tight as the factory lines, but they kept their shape well enough for what I needed. I think the trick is to bend them a little further than you need, and when dipping them in water, to cool them, hold the hose a little tighter than the tube holds it while pinching the other sides so it doesn't have a tendency to crush to get perfect bends.
Well, that is what I did and I am satisfied with the results, it gave me a good looking formed hose without the cost of the braided ones, and if I need a new one down the road, I can easily make one for like $15 worth of stuff.
The integrity of the hoses looks great, but I didn't test them in any way other than driving it around. I totally recommend this for vacuum line hoses, but I would want to test a little more before using this method for fuel injection or other higher pressure and higher risk applications.