I have the Logitech Harmony 688 - I got it because of great word of mouth and that it works well with DVRs. I have the Comast 6412 HD DVR, and the 688 has two extra FF/RW buttons that can be used for skipping commercials, DVD chapter skip & RW, etc. The Harmony 659 is cheaper, and doesn't have the two buttons.
Really easy to use for input switching etc. Just a matter of pushing "watch TV", or "watch DVD". Simple for wife and kids.
The Harmonys are good because you set them up via USB cable over the via their web page interactively - the LCD menu options are programmable and the screens can be paged down to include many additional options that say, the Denon 3805 would have. I plan on putting the "lip synch" feature of the Denon 3805 on the LCD, as I have this issue occasionally on the Samsung TV. Haven't put the 3805 on the remote yet, but I'll let you know how it turns out.
I got the best deal through Buy.com. Harmony's customer support is superb.
There is a coupon floating around for a 25% rebate, but you have to buy like, today! (I'm not endorsing this one, so you are on your own!).
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