I got it because when my son went to college, he got a MP750, and I really like it. Printer, Copier, Scanner... the MP780 is also a fax machine. This was two years ago.

If you do not need to have the machine on ethernet to share with others, take a look at the Canon Pixma MP530 or MP830.

http://www.usa.canon.com/consumer/controller?act=ProductCatIndexAct&fcategoryid=178

I can't talk too much to the Windows issues you mentioned, though I have used my work-issued Dell and HP/Compaq laptops to print to the MP780... I never tried scanning with them. I regularly use my G5 iMac flatpanel and G4 QuickSilver tower (and when my son visits, his PowerBook G4) on the MP780 (and he regularly uses his G4 PowerBook and iMac CoreDuo with his MP750 at school).

Rather than use print sharing, I just put a manual USB switch on the printer... because of the scanning feature (I think), all sorts of stuff gets strange when it is on an ethernet network.