This biggest problems with the multifunction units is the wireless printing. I've been through several HP's, a Brother, and nothing but headaches. Will work for a while, then show printer offline, or decide to quite working wirelessly, or only work with mac and not the pc's. The Brother 665cw print quality sucks. I loved the HP print quality but it was a pain with the wireless. Always on with tech support. My latest all in one printer is an Epson Workforce 600. It worked great right from the get go. PC's, Macs, no problems. The print quality is very good, though maybe not as crisp as the HP, but then the HP seemed to use a lot of ink. Haven't used it enough to give a good estimate on ink usage, but as far as I'm concerned working flawlessly without any issues trumps ink usage. I've always been an HP guy, not anymore.
Not sure how much printing you do, but if it's an appreciable amount, you should switch to laser. My ink costs have plummeted since I switched. You can get a decent laser multi-function from Brother or Samsung for $300-ish and you will have the print quality you want (way better than inkjet can give you) and you won't feel like your getting reamed every time you buy a cartridge. I got a Brother for my parents and they are very happy with it. The print quality is better than my Samsung laser SCX 4521F, and the cost was just marginally more.
Brother MFC 7820N Laser and network capable. Got mine from Staples for $200 with a $50 rebate. Everything worked right out of the box.