I love the Harmony remotes. But I must say, the 550 is the most problem-plagued piece of AV equipment I've ever owned. I am now on my third one in the past 18 months. Each one has been replaced under warranty, but that doesn't take away the fact that they are a piece of junk. Each of the first two had button failures within 9 months of receiving them. I'm just saying....AVOID THIS REMOTE LIKE THE PLAGUE.
Harmony One - Hitachi 51UWX20B - TiVo Series 3 - CM 4221 - CM 9521A - Onkyo TX-SR601S - Denon DVM-1815 - Panamax Max 4300