If you play under lights that will affect the drum’s tuning. If you play anyplace that has weather of any kind that will affect tuning. If you travel when you play that will affect tuning. There are one or two reasons to go tuneable. 
Thanks, Brian. 
If you’re going to get a drum, get a tuneable one. Skins change tension with the weather (humidity and temperature), in some cases drastically. Rather than wetting and drying the skin over and over, having a tuning system allows for quick adjustment and play. Same with tuneable vs. Non-tuneable whistles or flutes.
Its an interesting thread here (but good in a way) because it appears that there is a group of writers without so much experience with thee drum, and another group with an enormous amount. In that way, it may be sort of difficult to calibrate to who to pay attention to. I would suggest to all (as a maker and player since I can remember) that listening to people like Chris and Paul will do you a world of good, esp if your experience is limited.
Cheers!
Rob