I have played with the Brother MFC-5460CN a little bit and so far it is working well. The hardware and software setup is very simple. (I was a little disappointed you have to reboot OS X to install the software. I expect less reboots from Unix systems. Now "ps ax" shows me four server processes running in the background with Brother's name. Perhaps their experience indicates a reboot is the safest way to ensure CUPS is correctly configured or something like that.)
Brother's Control Center application displays an icon in the status bar at the top of the screen. There are a lot of options to take advantage of the scanner. You can launch a viewer application, launch an OCR program, attach to an e-mail, or automatically dump it into a file in a specific folder. There is also an option to copy a document from the scanner to an arbitrary printer. I expect to get the most use out of the scan-to-file option. The Control Center allows you to create default settings for a button on the front of the device, so I can configure it to dump scans into the Pictures directory one after another, and later review, rename, and organize them.
I found another annoyance in Apple's Preview application. It supports multipage TIFFs, but it has poor keyboard access to the trailing images. You have to open the Drawer and expand the disclosure triangle beside the "file" before the Next and Previous commands will work. This behavior is very different from how it handles PDF files. At first, I didn't think it saw the trailing pages at all! My QuickStep viewer is simpler, and I think less aggravating, because it treats multipage TIFF files as just another archive. The Next and Previous commands always work the same.