People having lag and interference issues are most likely plugging it into a USB 3.0 port which is known to cause issues with wireless kb/mouse.

Lately the lag has been extremely bad if it is working at all

The keyboard and mouse are very responsive; no lag at all.

Constantly getting frustrated with the horrible lag.

The keyboard has a terrible lag at times takes a couple minutes to reset then works for a while and lags again.

I experience some lag in response when interacting with it, especially when I am dragging the mouse

If it is not lagging, it just isn't working at all

But the lag from both keyboard and mouse made it unusable.

As if that weren't bad enough; it has a horrible lag between key-press and screen input, making it impossible to write with for any amount of time (writing this took some patience)

Cons are that it doesn't have a good reach distance and some lag when far

No lag, and Windows sleeps like a teenager

I love the keyboard, but the lag drives me crazy

Right out of the box, the mouse worked, but there was lag, and the keyboard did not work at all

2ft of the dongle to get it to work properly heavy lag or stops working at 6ft, the range i need it for

The only glitch I've noticed so far is the keyboard doing a weird lag once

This keyboard has the worst lag I've ever experienced.

This keyboard has terrible lag.

The lag on this is horrible.

Horrible lag

There is an irritating lag between keying an instruction and the implementation

The mouse and keyboard worked for a couple months but now all I get is lag from the key presses and the mouse response

Disappointing lag and connectivity issues, especially the keyboard

Pretty bad lag between the device and my computer, the mouse is often slow to respond.

Perfectly fine keyboard and mouse combo if there is nothing in the area that will interfere with 2.4Ghz signals, otherwise you'll experience significant lags, even when the keyboard/mouse are right next to the USB adapter.

you'll start to see very annoying lag, missed keystrokes, jumpy mouse etc

The lag on the mouse is so bad the thing is worthless, and the keyboard isn't much better.

There is a crazy lag between this keyboard (only the keyboard, the mouse is totally fine) and 3 separate laptops (two macs and one dell)

All to no avail, there are lags and times when you can't drag-and-drop or select text anymore.

Both keyboards suffered from bad lag time, phantom repeat characters during typing, occasional lock-ups and sometimes utterly unresponsive keyboards unless I restarted the machine or at least pulled the Bluetooth receiver out

Ridiculous lags and lots of times doesn't even register key presses

There's significant lag, sometimes it just decides not to type at all

and it's sooo frustrating and time consuming because the lag is terrible.

The keyboard is constantly losing signal and has terrible lag a lot of times or no response at all

Logitech usually does a good job and I've never had a problem with anything I've bought from them before but the outstanding lag and incorrect character expression with this keyboard has shaken my faith.

Keyboard has significant lag and stops working

The lag in the keyboard is enough to drive you crazy

Awful lag with mouse and keyboard also lags horribly

Disappointing lag and connectivity issues, especially the keyboard

the lag is unbelievable when it even registers the key-press

Keyboard has a terrible lag.

The lag on this keyboard and mouse make it completely unusable

This product is terrible...the time lag between typing and showing on the computer is inexcusable.

Too much lag, sometimes there huge annoying delay to text to be appeared on screen

We connected a wired mouse and then the keyboard got progressively worse (lagging behind while typing) until it finally just stopped working completely (batteries were replaced so that was no the problem).

No lag or any issues, would highly recommend for the price you can't beat this!!

Dislike the lag in the keyboard and mouse - very annoying and too often...

Fast shipping item works great no lag

Do not buy this keyboard unless you enjoy keyboard lag

Everything works as it should no complains

If this product works as it should, it's perfect

, this uses the standard non unifying adapter but works as i need

Bought a replacement as it doesn’t always work when you move the mouse or use the keyboard.

I burned the mouse and keyboard pretty good and they still work as if nothing happened

I stutters and stammers and is not at all drop-out-free as

Works as it should and comes with batteries :)

The keyboard works fine, but the mouse doesn't always work as it should.

I can type full speed as fast as I can and the accuracy is excellent.

It works as it should and easy to use I have it on my Mac.

All works as it should, but input lag can definetly be an issue

I would recommend this, as if it works as it should, it's a nice cheap cordless keyboard/mouse combo