The mouse has volume controls to the left of the left button, and a pair of up and down arrow keys positioned just above the thumb rest. This time, the volume controls are customisable, so you can set them to the kind of things you might want to do with a mouse, such as activate Exposé functions or Dashboard.
Both the keyboard and the mouse operate using proprietary radio transmissions in the 2.4GHz band. I'd have preferred a Bluetooth connection, if only to free up a USB port, though if you use your Mac's Bluetooth link for other things, such as a PDA synchronisation or mobile phone hook-up, you'll appreciate the extra receiver.
Wireless means both devices need their own power sources, and Logitech claims both sets of batteries last for up to six months - typically even longer - thanks to power-saving modes that kick in when you don't use a device for a certain period. You can see this with the mouse - leave it for 30 seconds or so and when you push it, there's a tiny but noticeable lag period before the cursor moves. That said, if you're typing, it comes back up immediately, and it catches up sufficiently quickly that you never feel it's being unresponsive.
I found I could easily use the mouse at over 3m from the receiver in Reg Hardware's radio-noisy office, and I'd expect better performance in a 'quieter', home environment.
At £60, the S530 isn't badly priced. Apple's own Bluetooth keyboard and mouse, the first set Mac owners looking to go cordless are likely to consider, together cost just under £80, and they lack the palm-rest and the extra buttons on the mouse. Apple's keyboard looks better, it's true, but Logitech's mouse is far more comfortable to hold and use. The S530 is a particularly good choice for Mac Mini owners, especially if you're considering living-room usage. This rig lets you sit back on the sofa and surf.
Logitech's Cordless Desktop S530 for Mac isn't the best looking keyboard and mouse set I've seen, and some elements - such as the nonetheless useful special-function keys - make it look cheaper than it is. But it works well, and Logitech's software makes re-configuration of the keys' behaviour a doddle.
What made this set for me is the MX 600 mouse which, while it may like the ultra-high resolution that gamers or Photoshop folk prefer - they'd want something like the MX 1000 - it's a good balance between price and performance. ®