I bought a Mac Powerbook G4 and, as it has Bluetooth built in, decided to eliminate a cable and buy this mouse. With the Powerbook there is no need to use the supplied USB Bluetooth adaptor; just install the driver, insert the batteries in the mouse and everything works.
The price has come down considerably in the past few months yet the feel and fit of the mouse reflects no compromise. It has a matt finish without annoying reflections, is large and has quite a pronounced "hump" in the middle but fits the hand well and requires just the right amount of pressure on the buttons. I was a bit less sure of the scroll wheel at first, which is soft plastic and felt a bit vague, but soon got used to it and, in the long run, find it more comfortable and less noisy than a hard wheel.
In extensive use the Bluetooth link is fine; I have noticed no lag, dropped clicks or, indeed, any other difference in responsiveness from the wired Microsoft mouse I used before.
The only problems I have remaining are with the driver. Although it integrates well with OS X Panther (10.3.4), as a new item in the System Preferences panel, and gives good control over scroll speeds and button mappings, it has a couple of limitations. The first, which may well be an operating system problem, is that the Microsoft driver button settings are overwritten, without any indication, by those in other Preferences items (particularly Expose) which happen to conflict with them, and I needed some trial and error to sort everything out. The second, more serious, problem is that there is no way of preventing a mouse movement waking up the Powerbook from sleep; thus bumping it by accident could drain the battery.
Those issues aside the whole package is well presented and being able to assign "Secondary Click" to the right mouse button is great, getting rid of the awkward combination of holding down Ctrl and pressing the trackpad button which Apple has implemented in the (dogmatic) absence of a second button on any of its input devices.