Where to install window sensors?

[killervette]

Typically, what part of the window are sensors installed for an Elk system? I was looking into the 3/8-inch 'Stubby' Press-Fit Magnetic Sensors. I assume you have to drill a hole in your window. Anyone here use these?

 

[BraveSirRobbin]

I use the small round magnets that only require a screw to mount along side the window frame (in lieu of a large hole) as shown in THIS How-To.

A lot depends on the type of frame you have (i.e. is there a gap available, do the sides fit "flush", etc...).