I have the Harmony 688. I absolutely love it! It is by far the best universal remote I have ever used. It controls ANYTHING. The online database is huge. If, by chance, one of your devices is not in the online database it has learning capability. You can even load TV listings into the remote!
The activity concept is wonderful. I can press "Watch TV" and the TV comes on, switches to "cable", receiver comes on and switches to TV and then ProLogic. Press "Play Xbox" and the TV switches to video 1, receiver to VCR then to CD, and the digital input is activated. All of the functions take ONE button push. All the basic activities (macros) are setup automatically using wizards with simple questions like "what do you use to change channels while watching tv?"... volume?... You can customize the basic ones and make your own as intricate as you want. I have never seen a remote this customizable. Every single button can be customized and any button that is not covered in the hard button array can be added to the LCD screen.
If the remote gets "confused" and out of sync the help button will fix it. It asks questions like "Is the TV on?" ... yes or no, "Did that fix the problem?" ... yes or no, and so on.
The best thing about this remote is that you program it on your PC. I don't know why no one else has done this. Programing on the PC is far superior to punching in codes on the remote itself.
I would recommend any of the Harmony remotes in a heartbeat. They are all very similar in functionality. It's really the button layout and egornomics that differentiates the models. I paid $80 for my remote at Newegg.