I could put her in a curb if I wanted to, but since she can't have a snaffle in her mouth becuase of her melanomas, I'm not sure if she could have a curb either. I might decide to try at some point since Arabs+curbs=DROOL, but currently, I just neckrein her in my bitless shindig and she does fine.
This is the kind of curb I plan to get if/when I get one (smrobs recommended, lol):
SS Hinged Ported Roller Futurity Bit 5in - Horse.com
And, this is THE bit smrobs recommends to people and uses herself (can you tell that smrobs is my cowgirl hero? Hahaha):
NP Sweet Iron Loose Cheek Western Curb Bit 5in - Statelinetack.com