I have the Fitbit Aria scale. I got it just before starting my pre-op diet. I love it. I have the info on my weight and percent body fat go to My Fitness Pal. I really like their graphs, and it's all automatic. It was great to see the rapid decline at the beginning, but it especially helps me see the downward trend when I seem to have plateaued.
My Fitbit scale and my digital kitchen scale are my two best tools in helping me be successful.