Chandelure is fucking great. End of discussion.
Actually no, that’s much too short. Let me expound a little. Chandelure has amazing stats — 145 base Special Attack, the kind you can start comparing to titans like Mewtwo. Decent defenses at 90 each, and a solid typing. I’d say Chandelure’s one serious weakness is its Speed, but it’s still pretty fast; it’s just not fastenough, needing a Choice Scarf to be able to safely kill a lot of potential threats.
On top of that, Chandelure has a good movepool and great abilities, in the form of Flash Fire, Flame Body, and fucking Shadow Tag, the ability that single-handedly turned Wobbuffet into a god in Gen 3 from his previous status as a joke in Gen 2. As a direct result, Chandelure is relegated to Uber Tier in a few places, but it tends to vary a lot since Shadow Tag is Dream World exclusive.
My preferred set uses Choice Scarf to turn Chandelure into a nuclear bomb, firing off Overheat before switching out with a teammate to take big bites out of opponents. If you don’t mind playing Ubers, Shadow Tag can be used to trap an opponent that can’t really hurt Chandelure (Choice-using Fighting- or Normal-types) and set up Calm Mind to go on a bulky sweep. You also have the option of playing more defensively with moves like Acid Armor or Will O Wisp, but it seems like a waste of that beautiful Special Attack.