I have used one of these for about 28 months now, and it has never let me down (unless you count running out of toner, which really is my own fault). It scans pretty quickly, and gets great resolution -- I find that 150 dpi is plenty for text documents, and it can go up to 9600 dpi for photos. It has a 35-sheet automatic document feeder, which I have found is big enough for most scanning projects. If you have larger batches of documents to scan, though, its software allows you to combine jobs into one large file (which Apple's native Preview app allows you to do anyway). For printing, it manages a respectable 23 pages per minute, and can do double-sided printing without the hassle of turning over your print job. My only gripe is that it cannot scan or copy double-sided documents without turning them over and manually collating the pages. I have not used these functions, but it can be set up to run on a network
Though it appears that Canon might not be selling these any more, they still can be found at a good price on Amazon. If you can pick one up for $300, I think it is well worth the price. Replacement toner cartridges run about $100.