Tossing my two cents in, even though we only have experience with the ol' Ruffwear (Webmaster, right?) that's still working for Gerry.  I had gotten out of the habit of using the harness because he hadn't needed support yet anyhow, and he was going through one of his crazy poop-eating-as-much-as-he-can-get-away-with phases (much easier to control when the leash is on the collar, though I felt bad about pulling on his neck at the same time).  Well, he hurt his shoulder and so I asked the rehab vet if she felt it would be better to get him back into the harness, or worse, or if it would make no difference.  She was in favor (not strongly, but not neutral on the subject either) because of the weight distribution.  My understanding was that the more of a puller he is (which he can be), the more helpful that is.  I have noticed that he is a much more effective "sled dog" (he fancies himself a Husky mix) in his Ruffwear harness .  But that's make sense, the better it is for their mobility, the more mobile they're going to be - haha!!! 

Gerry loves the "arm-hole."  OK, that's probably not true - he just loves his walks - but he lifts is leg up to go through it too fast for me much of the time. I can't recall if he knew it was for walking when he first learned putting it on though, but I was just thinking it might be easier to teach the use of it if you don't let them associate it going for a walk (which is so exciting!!!) until they have it down pat. Just a thought, if anyone is getting their first of that style.

After all the exercises/stretches the rehab folks recommended, I wouldn't be surprised if putting it on and off isn't good for range of motion too.