This is one area where you can compare the output of all three printers and see a difference. The 680 is grainy, but still good enough to get the message across. The 680 is quiet compared to older models, but it's louder than the 880 and the 870. Fortunately, you don't need to listen to it print for long - these printers are extremely quick. Even an image that takes up most of an A4 page can be printed on the 680, in Fast mode, in a little over 30 seconds.
Text is even faster.
I don't know what Epson has done, but these babies fly. The new crop can print at 2,880dpi. This ultra-high resolution makes a mockery of the resolution race. If you were to print an original image that had this resolution, not only would it take forever, but the quality would be similar to a lower-res print. Consumer scanners don't tend to go much higher than 1,200dpi, so original 2,880dpi images are rare.