I'm using a WW scale (its blue-not sure how many different types they sell) and I'm really not happy with it. I can get three different readings in a row. I changed the batteries, have it on a flat surface, and still can get pretty inaccurate readings.
I just got it yesterday actually. The regular one, not the one with the BMI and all of that. It is showing about one pound more than my old one...which is actually probably more accurate. I'll have to test out what NYFLAgirl said about it though.
I bought it, only because it was on sale and the cheapest digital at the time. It showed me about 2lbs lighter than my previous digital one and I used 2 8lb hand weights on it to "calibrate"and it registered as 15.9lbs instead of 16lbs so to me, it is pretty accurate.
I've been thinking about getting a WW scale - only because my cheap $15 scale from Walmart is crap. I weight 3lbs more than the scale at weight watchers.