Are listed sole lengths of 1/2 sized boot correct?

Yes, sole lengths listed for 1/2 sized ski boots are correct!
Almost all boots use the same shell for there half sizes as full sizes. That is, if an Edge boot in size 26.0 has a sole length of 305mm, that same boot in size 26.5 will also have a sole length of 305mm because it is the same shell. 1/2 sizes are made up for boots with thinner liners or footboards. As you might guess, the difference in a boot fit from 26.0 to 26.5 will be minimal, but the difference between 26.5 and 27.0 will be meaningful. Believe it or not, some boots only differ in the thickness of the insole (by about 1 mm) between a whole and half size. In other words, they are the same size.
Of course if this is still confusing to you (trust us, we understand), feel free to chat in, or give or Customer Service Department a call at: 1-877-589-7547!