The behavior is not present when the mouse is used vertically or horizontally, but it’s very disturbing and renders any Photoshop etc. action useless.

The behavior has been confirmed on Mac OS X Leopard and Snow Leopard on my part, with no change between the two OS.

The same skippy tracking can be observed on older versions of Linux and non-updated copies of Windows XP, which previously required a driver in order for the mouse to work correctly.

Newer Windows and Linux releases, from around Windows Vista and up, do not suffer from this problem at all. It looks like the mouse uses a different laser tracking mechanism not supported by Mac OS X.

I would have thought the new laser-based magic mouse would bring laser support for the G5 on OS X but it didn’t.

I bought this mouse before having a Mac, so I’m sad I couldn’t get it to work correctly on OS X since. I bought a Mac when Leopard got out. In fact, all I have is a Leopard upgrade DVD and my iMac packaging is still Tiger’s.

In any cases, if you are looking for a mouse for Mac OS X, definitely test it before-hand and make sure the manufacturer says it is compatible with Mac OS X. You might be tempted to think there compatibility is only limited to buttons, but it also includes mouse tracking, which is more essential than customizable buttons.

Definitely check for how well the mouse responds on your Mac in OS X versus Windows because Mac OS X supports much less mice by default than Windows or Linux, which come bundled with a larger array of drivers for these devices.

However since OS X 10.6.2 it’s driving me nuts.

I can no longer play OpenArena since the DPI-setting randomly resets itself from high to medium while playing. I have the same severe skipping that you’ve written about, which I did not have before. If that would not be enough, the controls just lag or breaks as if the online connection is interrupted. I often have connection errors during online sessions, but those do not seem to be caused by the connection itself, since I have the same problems in single player modus. Looks as if the USB is just over-saturated or something….

My guess was that the USB drivers in 10.6.2 are just broken, but I don’t know it for sure.

It’s a real shame… :(

USB Overdrive or any other 3d party program will not fix it, random jumping is possibly a firmware or hardware problem of the mouse itself.

Another person with the same problem: http://forums.macrumors.com/showthread.php?p=8294299

I also love the nice build quality of the G5; it’s something new for Logitech

New? The G5 had been on the market for over two years prior to this review. Granted, this review is for an updated version, but the differences (beyond an extra button) are minor: the design and build quality are the same as the one that came out in 2005.

I wear out the left click button on a mouse. With popularly priced Logitech mice, it takes about nine months before the clicking becomes erratic and highly annoying. I’ve been told that the standard Logitech mouse uses a microswitch rated at 1 million clicks. The Logitech gaming mouse claims 8 million clicks–so I’ll be enjoying it a lot longer.

One annoying thing though is that when iTunes synches with Apple TV over wifi it interferes with the mouse and it gets stuttery.

I use a G5 on my gaming PC and I love the weighting options. Solid hardware, shame Logitech can’t develop lean software.

It’s actually almost a blessing, considering how ugly and bloated Logitech software tends to be. Anyone who’s used a Harmony remote on a Mac (like me) can attest to this.