I found the PureFlow lacking the stability I needed.  The base was not widened so it was actually a little tippy for me.  Lovely inside, smooth and comfortable so you could actually go barefoot.  Cushioning not quite as good as the PureCadence 6 (which still wasn't enough for me).  Not enough for me anyway.  If you are not use to a shorter foot/heel drop this is only 4 mm and I could definitely feel the difference since I am use to 12 mm.