While Sony's excellent SMU-M10 is a travel mouse that tucks away into the slimmest of spaces, this travel mouse is a bit more cumbersome. It's the same size as a desktop mouse, so you'll need a thick laptop bag to avoid creating a bulge that presses into your Mac.
It also tracks across the screen rather skittishly until you figure out how to slow it down (hold down the three buttons for a second or two). The default track speed is too high for anyone not trying to shoot aliens.
The scroll is optical on this mouse, which feels a bit weird. The eye at the front of it reads your finger movements and moves the page up and down correspondingly. We must admit that we prefer the tactile qualities of a scroll wheel and its finer precision.
Compared to Sony's SMU-M10, this mouse comes away the loser. It's just a little too big to tuck away, and a bit gimmicky with that optical scroll.