Ergonomically the LS1's shape is reasonably comfortable, though it can't match the moulded contours of dedicated right-handers like Logitech's G9 or MX Revolution - admittedly far more expensive mice. Its rubberized lower section does provide a kind of thumb-rest, but we wish Logitech would have extended the rubber to the small cut-out matte sections on both sides of the LS1. Still, as long as you're not using a wrist-rest mouse pad, this Logitech provides a secure grip.
Three small Teflon feet ensure the LS1 slides along smoothly enough and its laser sensor is never less than accurate. Unfortunately, its button action is not as nice an experience. Though the buttons give a defined click when fully depressed, the LS1's left and right buttons feel just a tad mushy. Also, if you press the left one just after right-clicking it feels like the left button snags a little, which can be disconcerting.
Logitech's SetPoint software is as good as ever, with some intelligent default choices. Clicking the scroll wheel, for example, brings up a zoom pointer, which lets you use the wheel as a zoom control. As ever, if this doesn't suit you the scroll wheel is fully configurable, meaning you could make the LS1 a five-button mouse with two-way scrolling.
Overall, the LS1 is by no means unusable, but it isn't a patch on other Logitech mice. On the other hand, with an MSRP of £19.99 it's also one of the cheapest and it's still a step above most bundled mice. However, for the £14.99 it demands online you can easily get better mice from Microsoft (like its ergonomic Wireless Laser Mouse 5000 for only £2 more) and even Logitech itself, leaving the large range of colours as the only reason to purchase the LS1 over similarly-priced alternatives.
Logitech's LS1 is as basic as it gets and while a step above most bundled mice, it's not particularly comfortable to use either. Basically there are better mice available for the price, though if you must have a mouse to match your pink/blue/white or other hue of netbook there are few alternatives.