As for adjustability, this vest is pretty good. As a female, I needed more room up top than I did on my hips and mid-section. it looked rather masculine on me. I got around this by closing the side zippers on Large, then using 4 medium/large VERY CAREFULLY placed safety pins 2 on each side) on my waist side (to make those areas "medium")....and it looks much for feminine now!
I would love to give this 5 stars...unfortunately, it doesn't allow you to turn off the heated zone on the neck (which was a bit too warm for me even on low). I tucked the collar completely under, but the wires run evenly across both sides of the material, so all that did was shift the heat from my neck to my very upper back (again, too warm even on low).
If there were a way to allow the user to move the heating elements from the neck and put them into the middle (thoracic) section of the back, I would LOVE this vest!
The alternative suggestion would be to allow the user to access the wires (hidden pockets?), so they can disconnect and reconnect certain sections as they would like.
That said, I also bought the vinrooni one (which also had the heating elements in the wrong areas, and in much worse placement areas), and this one is thicker and higher quality, but it uses the smaller jacket zippers instead of the large heavy duty zippers that last forever (which the vinrooni one does).
Another positive to this one is that the heating elements in the lower back and front pockets are AMAZING for all sorts of lower back AND belly/digestive/feminine cramping.
It won't let me give it 4.5 stars, which I believe it deserves. While it could use some work, I would DEFINITELY still recommend it for someone who has osteoarthritis, or is just generally cold. The instructions make it sound more difficult to use than it is (or I never figured out how to use the "auto" mode. I held the button for 3 seconds, and it came on, and I clicked the button once to get to a color, then clicked once again to get to the next color, etc.
Red was too hot for me...so I liked to rotate it between blue (medium), and green (low).