I understand that in terms of the core rules to run games
- D&D 3.5 has: Dungeon Master's Guide + Player's Handbook + Bestiary(s)
- Pathfinder has: Core Rulebook + Bestiary(s).
Pathfinder has a Game Mastery Guide, but I understand this contains extra information for writing/planning campaigns rather than running games.
I run Pathfinder games and I'm considering buying a 3.5 DMG. With the equivalent of the Pathfinder DMG combined into the CR, do I already have all of that information? Is there much practical advice for GMs from the 3.5 material that would apply to GMing Pathfinder that would make it worth buying?
Is there any non-rule content (like practical advice for running games) in the DMG, that is missing from the Core Rulebook and GMG?