You can use heat shrink tubing on the ends since it will fray when you cut it to length. The split design holds its round shape and the split ends overlap each other. I wouldn't think you'd need anything other then the regular factory wire holders to secure it.
The plastic convoluted tubing is harder and would protect the wiring from an impact more than the stuff I posted. The stuff I posted is very flexible. It's basically just to keep the wires together and to make them more attractive. The convoluted tubing might still be better for a hidden area that passes through a bulkhead. I don't like the look of it in visible areas.
I just have a very short piece of it that was used somewhere on a later model vehicle I used to have. I don't remember what it was any more. It's good looking stuff and will expand at least to 4 times its diameter. I haven't bought any in bulk to try yet.