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I would worry about things inside the tire causing damage to the tube. I had friends that had a lot of trouble keeping tubes from getting holes in them with some professionally built tires. In the end they decided that when the tube was inflated it was pressing against the liner enough to cause the screws to poke through and puncture the tube. They had to back out dozens of screws, file the tips flat and reinstall them.
I could also see the edges of the liner being an issue.
My solution was to run ultra heavy tubes. Knock wood, I've yet to have a problem.