Those are the ones we use, too. They are well-worth the cost.
Herm-Sprenger finally fixed something I always considered a problem, namely, the direction all of the prongs face on their collars.
They now have a version with a central link so the prongs face opposite ways and apply even pressure around the dog’s neck rather the ‘drag effect’ the other kinds cause.
They’re hard to find and cost more but they work 100% better than the standard H-S prong collars.
http://www.things4yourdog.com/product/45-6423B
[yes, I am *that* picky...why do you ask?]
;D