| They're almost the same size. The Lite is lighter- probably because it takes one less battery. The backlight is a little different. It has a whiter hue to it on the Lite, versus a green one on the Flash. The Lite's font is WAY bigger. The Lite doesn't display time all the time- you need to press the C button to get the time. The Lite has a larger memory and you can scroll backwards and forwards. The Lite has 7, 14, and 30 day averages versus just 14 on the Flash. The Lite has a yellow strip port to make it easier to aim. The Lite also added rubber grips.
And those are the differences. Overall, I loved my Flash and the Lite is a great improvement on it. | 
