Wolfy Dog, looks like it got off track a little......
6 GSD's. Have used prongs on all of them. This is the one I use: Herm Sprenger Stainless Steel Snap Prong Collar w/Extra Strap - dogsportgear.com
I like it as it does not tighten but still gives additional control.
I too prefer positive methods and never use a prong on a dog under 7 or 8 months. The only time I use the prong is when walking multiple dogs. I do not use it to train heel or other behaviors.
I am only about 125 pounds and yes, my male can pull me over if he chose to. Havoc is a great boy and very obedient but there are times when the prong is simply another control tool just like a gentle leader or front cliip harness. I have never had a dog create a negative association with it. I suppose that can happen if you are using the prong as a correction collar in the prescence of things the dog shows interest in. If the dog is accustomed to the prong this should not happen.
URO3,UCD Aleshanee Windridge "Kayos" CD,TDX,RE,CGC,HIC,TC
PTE,AG2,AN,URO3,UCD Xtra!Xtra! V TeMar "Havoc" CDX,GN,RE,CGC,HIC,TC,BH
UACH,URO1 Tidmores Rising Star Lydia "Mayhem" CD,BN,AX,OAJ,NF,RE,HT,TC,CGC,
Lucky, Wolf, Max