I've used all three at various times for various reasons and have never found the dogs to be more difficult to train to walk to heel on one rather than the other. In saying that mine are taught to walk at my side, slack lead but I use the palm of my hand fingers outstretched in front of them so that they know not to move forward. These days they have flat or half check. Don't do training classes so I just please myself.

Harness user here
Its very important that the correct type of harness is used and correctly fitted too - harness type and fit do make all the difference
The Pets At Home type which clips up behind the shoulders and has two rings for the lead to clip to are pretty useless for good control so if that`s the type you have I`m not surprised you are not having much joy with it, [ just guessing ].
If you have a Trail type though and are not finding it much good, if you can take pics of it on doglet of front, side and top views I`ll be able to tell you if the fit needs adjusting

Thanks Patch, it wasn't a PAH one it was one of those fleecy lined ones. He didn't like it and I did feel he was learning to pull into it so went back to my flat collar...no one can say I didn't try!

I don't expect my lot to walk to heel, I'm so used to training to walk ahead now it feels a bit cumbersome if they are at my side! I just want them to walk with a loose lead. Cosmo does and is starting to correct himself if the lead goes tight...well at least in his more calm moments he is anyway!

I put them in the lower position as close to their shoulders as possible.

Thanks Colin!!

Why did you ask?

Are you having problems with your dog on a half check?

i dont train loose lead walking!! however my current Gadget of choice top stop pulling is a dogmatic headcollar.

I've tried all 3 as well as a slip lead but Flynn still pulls like a train no matter what he's got on. I just stick with a flat collar now.

Flat half-choke here, if they start pulling, a quick gentle jerk on the lead does the same as a choke chain and it's kinder on their knecks.

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