"What fantasy RPG other than D&D have you enjoyed most? Why?"
Not that I wouldn't love to talk about Pendragon again, but goddamn Iron Kingdoms is so badass and totally has a 1d4chan page I can link to. IK was originally released as a setting for the d20 D&D ruleset, then progressed into becoming the completely amazing wargame Warmachine (ha! linked again!), then was popular enough to regenerate its RPG system based on the mechanics of the wargame. Holy shit that's like a Möbius strip of everything good about tabletop gaming.
Iron Kingdoms could be classified as a Steampunk RPG set during the Industrial Revolution, if the Industrial Revolution was catalyzed by magic and the need to drive tyrannic necromancers from a coalition of enslaved lands, using giant steam-powered robots. That brings me to the first thing I adore about the setting: its rich history. The various countries and citizens of Immoren have a good 800 years of back history, all painstakingly created with the kind of immersion that high school history books only wished they could pull off.
What's really impressive, though, is that the written lore in the core book only really covers a small portion of what is likely a very large planet.
For reference, Western Immoren seems to be roughly the size of our Europe.
The d6 dice mechanic may seem like a bit of a letdown compared to various other systems that utilize multiple polyhedrals, but the simplicity of the system allows for new players to pick up and play quickly and- best of all- allows the IK ruleset to work nigh-seamlessly with the WarmaHordes wargame, creating all kinds of options for adding enemies from various armies, rather than relying on the bestiary of the core book which focuses mainly on enemies you won't find in WH. So perhaps they planned all along for this curious synergy.
Which is awesome.
Lastly, I must talk about CharGen, because I love CharGen. Iron Kingdoms features a unique variant on character creation, starting off new heroes with a mechanic that is almost dual-classing, but creates narrative options from your choices. So instead of choosing to be a fighter, or a thief, or a magic-user, you choose two Careers (Like Knight, Cutthroat, or Warcaster) at the outset, and these define the weapon and non-combat skills you both begin and progress with. What's really cool about the system is that each choice made during CharGen informs to your character's origin and potential progress, so by the time you've got a filled out character sheet you'll have a few hints towards your hero's backstory.
It's really a great game, and you should totally check it out.