I am a mouse lover and have a habit of always looking for the next best thing (too expensive a habit!). Anyways, this mouse I got by accident (didn't see much fanfare in the press) but it is by far the most amazing mouse device I've ever seen. I can't seem to get the side-by-side scrolling to work but the touch sensitivity instead of the scroll wheel is the best innovation I could imagine.

Logitech should promote the Hell outta this thing!

Click that BUY button and get this.

I have a big notebook computer- the HP Pavilion ZD8000. It's a desktop replacement, and although I have a Mac at home I use quite frequently, it's my laptop that's the workhorse. Before my ZD8000, I had an HP ZD7000 (they are both big 17" display monsters), and although I used 2 different wireless notebook mice with that one, I also wore out the touchpad. Literally. Needless to say, I use my mouse a lot.

Here are my issues with most wireless mice: They tend to be picky on which surfaces they are used. Most have that lag time between the time you start moving it, and the time the receiver registers that it's being moved (damned annoying, that one). Many, in lieu of the previous undesireable effect, have resorted to making the user click the reset buton on the receiver and/or the mouse itself. (I have a co-worker in fact, whose mouse reset button has pen ink all over it as a result of constantly resetting it with his pen because the mouse manufacturer made the reset button inpenetrable by human hands.) Additionally, the USB receiver dongle is so big sometimes, that you can't help but bump things into it, causing it to either break completely, or stop working temporarily. Sometimes, you just lose the thing all together. Quite frequently as well, notebook/travel sized mice are too small to be comfortable.

The Logitech V500 is a winner. The Reciever is housed in the mouse body for storage. Although it's pretty flat when it's turned off or stored in a briefcase, it gets larger, and more "mouse-like" when turned on, thanks to it's built in incline elevator (the mouse uncompresses). The optical tracking is SUPERB. It ALMOST works on glass- quite a feat. It tracks over carpet and shiny surfaces. You don't lose the dongle, because it is stored in the mouse itself, and you never leave the mouse on when stored, because you naturally compress the mouse to make it as small as possible, which also turns it off. There is no lag whatsoever, and I have never had to use the reset button. I have never been more impressed with a notebook mouse before.

One last observation: As I mentioned earlier, I have an HP ZD8000 notebook. On the right side of the notebook is a small bay for a USB flash drive. Turns out that the USB receiver dongle fits neatly inside of it, so now I never have to plug the dongle in, nor do I have anything sticking out onthe side of my laptop- I uncompress the mouse, and I'm instantly on. Highly recommended.

In comparison to all other mice I've worked with on the market, the V500 definitely wows in cool factor to date. But does it have both form and function? Absolutely not! This is not an easily pleased, girlie-man reviewer but a road warrior who lives and dies by traveling and working on a laptop daily. I don't compromise on my review, summarized here for your consideration.

PROs:
-Braggin' rights. Especially the price.
-Accuracy: V500 is more accurate than any other Logitech/Microsoft wireless mice I've worked with but a corded mouse is still more precise in cursor movement.
-Surface handling: It's the ONLY optical mouse I have tried to date, that will handle the alternating pattern surfaces I have work on without jumpy cursors.

Cons:
-Discomfort: It's simply too small to be comfortable and I've got small hands. After half an hour of use, I felt noticible discomfort. Even compared to Logitech's own Wireless Optical Mouse for Notebooks at half the price and better ergonomics.
-Scrollpad slow: Simply not as usable as a decent wheel. Cannot scroll thru pages in a flash and stop on a dime to scroll slowly line by line as a decent wheel can.
-Scrollpad inaccurate: horrizontal scrolling and accidental scrolling occurs frequently since the scrollpad is simply a touchpad. Especially given the small size of the mouse, once you take your hand off of it to type, then when your hand comes back to the mouse, your fingers would easily make unintentional contact with the scrollpad, causing to scroll accidentally.
-Scrolling click sound annoyed my co-workers in a quiet environment. CANNOT be turned off.
-No better portability. In its included ugly pouch, V500 is as big as most full-sized optical corded mouse without the cord. Travelling with a laptop and a mouse daily, I find no advantage between a $5 OEM corded optical mouse and V500.
-Scrollpad calibration software affects the settings for your existing touchpad and pointing stick. And calibrating your other pointing devices will also affect the settings of the V500. After calibrating all the devices back and forth, and thanks to the unpolished SetPoint software, I have to settle for a cursor speed too fast for my pointing stick, too slow for the V500, and too inaccurate with my touchpad. Isn't it inronic that the V500 scrollpad, my laptop's touchpad and its pointing stick are all made by the same manufacturer?
-Software bug: I have to recalibrate cursor speed (all other settings are fine) in WinXP's mouse setting after each reboot.
-Value: How much are you willing to pay for potential wrist/hand cramps, low usability plus all the above irritation?

Bottom line: Once again, a decent $5 OEM desktop optical corded mouse is the preferred choice of a real road warrior over the so called "Notebook mice". In fact, this mouse is even less usable, more costly, and immensely more aggrevating than Logitech's previous attempt. If not for such a sleek design, and the fact that V500 are perfect gifts for VPs who are given $4000 laptops to play Minesweeper during board meetings, I'd tell Logitech to shove the V500 up where the mouse keeps its USB receiver because this is nothing more than another attempt to capitalize on the mobile professional trend with yet another high priced, low usability product.

Actual usable alternatives for mobile professionals: Any desktop corded optical mouse with scroll wheel. E.g. Microsoft Wheel Mouse Optial Mouse, Logitech Optical Mouse.

I wanted a mouse because I need one while I'm Wi-Fing in meetings. I bought the V500 because I like that it's wireless, that it collapses, that it stores the USB receiver in itself, that it has 4-way scrolling, that it's small, and that it works on any surface.

Okay, but, initially I found that it hurt my wrist - less so over time.
I find that in meetings the left/right click noise is so loud it's a bit disruptive.
I'm constantly inadvertently triggering the scroll-up sensor. It usually doesn't effect my work but its repeating click noise is always going off, softly.
I think it's a decent power draw on my battery - so I don't last as long off AC in my meetings.

I didn't like the L/R-scroll response but all I had to do is adjust the setting in its SetPoint utility.

I would have liked having "back" and "forward" side buttons like the other Logitech mice have.

That said, I still use it because I still think it's the best product available - albeit embarrassingly expensive.

It gets a lot of attention and it serves what I bought it for pleasingly enough.

The touch sensitive wheel is a joke... not having the tactile feedback is a big disappointment for me. I like the size, but too flat/slim to provide ergonomics. I have to pinch the mouse in order to move it around and as a result, my fingers and wrist were hurting!! I ended up taking it back to OfficeDepot and got a Microsoft Wireless Optical Mouse for less than $30. It only uses 1 AA unlike logitech's 2 AAA(costly) and very much more comfortable. I forgot to mention... When i bought the logitech mouse, it was missing the receiver that it was supposed to come with!! Unbelievable... Went back and got another one that did have it. This is all I have to say,,, I wouldn't buy it if I were you :)