Of the two, I'd probably lean towards the Canon. I used Canon inkjets exclusively (still have a large format photo printer) and was very happy with the quality. I was going to go Canon for my laser, but I needed duplex scanning and copying, and Canon only had higher end business MFCs for that (like in the $1000 range), so went with the Brother. You should check Canon toner prices though - I don't know if they are higher than Brother, HP, etc. If outrageously high, you might want to wait for a sale on an HP or Brother.
Also, don't confine yourself to Staples. Look at Office Depot, Best Buy, etc. They were all outdoing Amazon when I was buying. For the printers on sale, anyway.