Usually a GM, rarely a player. I prefer science-fiction and modern/urban fantasy over medieval or high fantasy. I'm currently running a game in the Robotech/Macross setting using a highly modified version of Dream Pod 9's Silhouette system.
- FanPro's Shadowrun (Played and run all versions before 5th Edition; haven't had a chance to run 5th yet.)
- White Wolf's Changeling: The Dreaming (Eagerly looking forward to the 20th Anniversary Edition.)
- Dream Pod 9's Silhouette (I run Robotech/Macross, but DP9's Heavy Gear setting is fabulous, too.)
It goes without stating that a DM can change whatever they'd like, so citing "DM's prerogative" makes any answer moot. The DM can always do whatever they like, so using it as justification just weakens an answer. Interpreting logic and word choice is a different matter.