SmartTool Level vs Zircon VideoLevel

[Andrew Sarangan <europabuilder@yahoo.com>]

I am looking at purchasing a digital level. It seems
that everyones favorite model is the SmartTool
manufacturedby Macklanburg-Duncan. Amazon.com is
selling 
these for $99. However, there appears to be another 
electronic level made by Zircon that is only $40. I 
don't know the difference between the two. For such a 
large price difference I am assuming that there are 
large differences. Anyone know?