Harmony 688: The Reasonable Choice
This is the model for the average person. It's complete enough to meet all requirements, even with very sophisticated installations. On the other hand, it operates on four batteries whose life is not very long. Plan on replacing them every two months if you use it frequently. The display is black and white and has only four entries for functions specific to each device. It's a little less practical to use, though the difference isn't dramatic. The silvery look is less successful than that of the 880/5. It's more cheap-looking. But it's also available in a black version.
Ergonomics Above All
On the other hand, this unit has the same commands, placed just as intelligently, if not more so than on the high-end model. The rubber buttons may not be as pretty, but they have better grip and are very easy to see, especially with the powerful backlighting. Using this remote control is always a pleasure and, ergonomically, it is exceptional.
The Right Choice?
If you don't have thousands of personalized commands, the 688 is amply sufficient, and it's even more ergonomic than the 880. But the color display and classic looks are enough to make me choose the top-of-the-line model. The price spread is 100 euros in Europe, and that makes the 688 clearly the best compromise. The difference is reportedly only $50 dollars in the U.S., which would tip the balance in favor of the 880.