I honestly think that the head halter is the worst possible temporary fix to your problem because it could cause serious injury to your dog. Imagine walking along nicely on a loose lead, then she spots a cat and takes off - hitting the end of the lead and snapping her head around. Ouch!
Suzanne Clothier has a fantastic article on her website, titled "The Problem with Head Halters" you may want to check out --> Flying Dog Press - Suzanne Clothier - The Problems With Head Halters
If you need a "quick fix" to prevent your dog from dragging you down the road when she sees a cat (or squirrel), a prong collar would be a much better - and less harmful - way to go because it does not cause her to bend her neck as a weird angle when she hits the end of the leash and you need little body weight or strength for it to correct and stop her.
As far as changing the behavior instead of a quick fix ...
Right now, when your dog sees a cat and takes off behind her, that's extremely rewarding for her and great fun. You can correct her from taking off by means of training collars but the real challenge is being more fun and more rewarding than chasing the cat.
Do you have a favorite toy that uses her prey drive in play? Like one of those stuffing-free furry toys that squeak? They're a lot like prey to most dogs because they flop around, they can shake them, they make noise. If you can get her attention with that, use that in your favor by engaging her to play with the toy if you come across a cat.
You mentioned you can walk past them if they don't suddenly dart out ... that would be the ideal time to engage the dog with the toy, when you have a cat just sitting somewhere. Make the toy interesting and reward the dog for focusing on you by playing with the toy. (Playing tug would be great for this, especially since you can do it while walking.)
You want her to associate seeing cat (prey) with playing with you (and your prey).
At least that's worked for me.