in areas with cold winter weather the work and hassle of spring and fall window unit removal can become a major issue....

either remove the unit and store indoors, or leave it in and put up with drafts or the cold conducted indoors by the window unit....

in the summer a window unit means you cant just open the window on a nice day......

and when the weather is very hot and your trying to just run the bedroom window unit while your sleeping you may have to turn it on hours earlier to not only cool down the room but remove the excess moisture / humidity...

I bet anyone here that believes window units are better has never lived with central air.....