So just for you, I attempted to put on the harness this am and look at the results! See the attached picture. Again, I am not a fan of the carpet but look how she blended in - If I am not mistaken, it could mean the temperature was correct or at this point, she was showing emotions (she was happy at this point).
The wing on the left side actually got in the way of her walking at times.
Rocky still wasn't a fan of putting it on; she pooped on my friend who held her-LOL
Rocky didn't show stress marks, she simply didn't want it. Rocky will let you put it on, she just didn't want to keep it on but today was a FIRST!
Rocky didn't dart off but looked around for like 2 minutes - she then walked then ran, she felt the area out and did better than anticipated. As this isn't my home, I couldn't let her lick everything to ensure safety/comfortability too much - LOL Rocky is more interseted in the window!
Best of luck!