I have used the halti with great success. When I first started training classes, my instructor asked all students to use one. During the entire course, we used haltis. My boy was aprox 7 months old. Our next level classes, we didn't.
In the beginning he faught the halti. Just like a pup fights the collar for the first time. It did take some getting used to.
I can now walk my 92lb intact, 4 yr old male dog without him pulling at all. He doesn't lunge. He doesn't hesitate when we walk. He doesn't stop to sniff and mark. He walks quietly and calmly.
If I am going to take him to a crowed area, I'll put the halti on him. Not because he needs it, but for the same reasons Chip18 mentioned. While wearing the halti, folks think it's some sort of muzzle and they don't drag their hands all over him as we walk by.
Hondo Von Dopplet L Bauernhof "Hondo"- GSD
Lilie's Tug McGraw "Tug" - Golden Retriever
Maggie - Mini Dachshund (Rescue)
Lonestar Pivo - Texas Blue Lacy
Ashe - Barn Cat
Katie / APHA