The difference in the sidewall will be hardly noticeable. If you hauled loads every day, it might make some difference. I always made it a practice of using a size smaller tube than the tire...an 8.25 tube in a 9.00 tire. On the original installation, it will make no difference. However if you have a flat and reinstall the tube it will have probably stretched to the point where it will fold. Folds in a tube cause a leak in almost no time. We change our own tires and did for the public as well until the mid 70's. I would venture to say that more flats were caused by folded tubes than by nails.