HR21-100 here that has been ridiculously sluggish with the UI and worse with IR response. I use a Harmony 880 so RF is not an option. Received the new Software yesterday and it seems to have gotten a lot better. This could be due to the unit resetting as a reset usually will help a little (at least for a couple hours). I haven't had a chance to test it today, but time will tell if the update helped.