The difference between most of the Canon printers are a couple of features here and there. I don't have the 810, but I've had the MP530 for 6 months or so. I'm very happy with it despite the fact that it goes though ink a little faster than other printers I've had. The bundled software is also good. That was a huge factor for me when shopping for a printer since I don't like when printers come with a lot of useless software. No bloat here. Hopefully someone else will chime in with specifics on the 810. Hope that helps a bit.

The PIXMA is a decent printer but I've personally had a lot of bad luck with their cartridges in the past. If you care for an alternative the HP C6180 has been great for me.