I've been test driving the Harmony 520 and have been disappointed with the lagtime between pressing a button and actual response. Do all of the Harmony remotes suffer this limitation? Are there models that are snappy like the OEM remotes? In particular, I'm interested in the 676, 680 or 688 but am open to others.

I'm not sure about the 520 but on the Harmony 880, there is a way to change the following settings:

Power On:
Inter-Key:
Inter-Device:

Power on: Changing it allows you to change the response time for powering a device on or off.

Inter-Key: Changing this allows you to change the response time on the device and your remote. ** Your inquiry

Inter-Device: Changing this allows you to change the response time between the response time on the devices.

I actually just asked a similar question about my response time from my harmony 880 remote to my cable/dvr box. Changing these settings actually made a difference. No lag time!

You can also change the number of repeats for each device in your configuration. This affects the number of times that the remote will send each command when you press a button. I think the default for the Harmony is to set it to 3 for each device, but my devices get by fine with the repeats set to 2 (and there is a noticeable speed increase for some devices).

Here is something I found.

Similar to this issue. I figured I just post it so for other users that can mock the same thing. "How to fix slow response on Logitech Harmony 880 Remote Control with Tivo"

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1. Setting the Inter-Key Delay to 0

First set the Inter-Key Delay to 0. If this causes problems you can set it a bit higher, but 0 works for me. I also have Inter-Device Delay set to 500, but this is not important for what we are trying to do here. So to change this setting, which defaults to 500, from the Harmony Home Page select the 'More Options' link next to the Tivo device (not the tivo activity). The Device Options page should appear, from which you should select 'Adjust the Delays (speed settings)'. In the Inter-key Delay box, enter 0 and click Next, then click Next again from the next page.

2. Setting command repeat count to 0

Secondly and lastly set the command repeat count to 0. So to change this setting, which defaults to 3, from the Harmony Home Page select the 'Troubleshoot' link next to the Tivo device (not the tivo activity). The Adjusting Setup:Device Problems page should appear, from which you should select 'Show me more problems' radio button and then click Next. On the next page, choose 'TIVO doesn't appear to receive every command correctly.' and click Next. On the next page select 'The device responds too much to some commands (for example, volume up increases the volume too quickly).' and click Next. A list of numbers 0 to 5 will appear. This is the number of times the remote will send a command to Tivo which defaults to 3. Set this to 0 which works fine for me. If you have problems with this try increasing it to 1.

And that's it. Once I changed these settings, my tivo responded to my harmony 880 remote as quickly as it did to my tivo remote.

A couple more little tricks

To facilitate quicker fast forward and rewinds, I mapped the up arrow and down arrow respectively. I just found it a little difficult to quickly locate the fast forward/rewind and play buttons.

Since I also have a ‘Tivo Stereo’ activity, I added a custom button to lower the volume on the tivo. This also works with other activities like DVD. I tried just muting the tv, but the tv leave the word ‘MUTE’ on the screen.

Thanks for the tips. I had already lowered the interkey delay, and also came up with the "muting" idea, but I had not experimented with the repeat count on my 880. Now my 13-year old son may be willing to give up the TiVo remote for the "cooler, but way too slow" Harmony.

I have never found the repeat count option. That explains why my zenith TV responds with massive volume changes.

Why is that option so buried??

Thanks for tips Nutsnbolts. I also didn't know about the repeat count option. My TV volume always changes by 2 increments with each press of the Harmony volume buttons and it always annoyed me. I'll give it a shot.