Orange v's grey is quite a jump. Most people who want orange want to be highly visible for some reason (safety boat etc). I think I would take some convincing that a "good reason" for wanting orange was outweighed by a risk of fading.
Stored outside 24/7 in bright sunshine then orange tubes do tend to go a bit pink over time. This can be partially or totally reversed using a product like rib revive, and then the rate of fading reduced using a protectant coating. Searching here for "traffic film remover" or "TFR" will also reveal alternative cleaners. If it is really bad then wiping down with "gun wash" (spray gun cleaning thinners) is supposed to help too.
Obviously though prevention is better than cure and keeping the boat covered when not in use would be wise, particularly with sensitive colours.