You know in Singapore we had abandoned the Imperial System long ago, in the 60s. Ever since, we're using the metric system, milimeters, centimeters, and meters. In architecture, we always used milimeters (mm) as the accuracy count is more precise as it rarely has decimal or a quater.
Really? I'm suprised that you say the Imperial is crappy.
Well I have not tried using Imperial system, but I know how to use inches and feet well, its pretty relative in pattern.
I use the Metric system (mm) in Sketchup when I make any complicated study models all the time.