I currently use a Withings scale, but any scale that can log to the internet and produce a weight loss graph is great. There is varying advice on this, but I weigh myself every morning. The minor ups and downs are smoothed by a moving average. I don't expect the scale to trend downwards every day, but I have enough data to see movement in the right general direction.
In that sense the logging feature is key. When I used a regular mechanical scale in the past, it was sometimes hard to remember from day to day what was going on, and see a trend. You get caught up in the micro-movements from day to day. Again, the graph's moving average takes care of this.
