I just bought a cue w/ purpleheart in it, which I know can darken over time. The cue stays in my basement where it would not receive direct sunlight but would get some filtered light, depending on the time of day. Is it fine to leave it in my cue rack or should I store it in my case? I wonder if the risk of the wood growing darker is greater than the risk of wearing out threads (it's a radial pin) on a shaft that's taken on & off every day for years.