Contour tinted, dual-glazed, thermo-insulated window

[MutinyGuy]

This is an option on the new Adventurer we just ordered. The coach comes standard with tinted, dual-glazed thermo-insulated windows...can someone tell me what "Contour" means in this application and is it worth the upgrade?
Thanks all for any information you can provide!!

[HOHDR]

Like some side windows at the rear of minivans, contour windows fit flush to the side against an internal gasket, as opposed to standard windows with an external frame.

Contour windows don't slide. They pivot open from the top, with the open part at the bottom. This might allow the window to be open during a light rain, but the primary purpose is a sleeker look.