I bought the Logitech M505 little over a month ago and sofar I am very impressed. Order was placed with amazon.co.uk and although on this particular occasion I was dispatching to a non-UK address the delivery estimate was easily met.
I bought this mouse as an accessory for my laptop. Being on the move quite a bit I was getting tired of using a touch pad so I wanted something smaller than normal, easy to use, and overall easy to transport. I have found that the M505 ticks all of these boxes. The mouse is not as small as some other lap top mice without being to large to carry around in the lap top bag. It fits well into the palm of my hand and all the buttons seem of sturdy build quality. The mouse came with batteries which sofar are lasting well. The receiver is tiny and can be stored either in a USB slot in your laptop (little chance of getting caught) or in the mosue its self in the battery compartment.
The M505 was easy to install on Windows 7 64bit, just your run of the mill plug and play. It is adequately responsive for a laptop mouse and performs all the day to day functions I had in mind when I bought it. If you do have problems I have found Logitech quite good to deal with in the past. The mouse swiches its self off if not used for a while in order to preserve battery life and I am happy to say that upon moving it after it has gone to "snooze" the response lag is quite minimal.
There are a few things which I think could have been impoved on with the Logitech M505, the battery cover seems a little flimsy and it would have been nice if it had come with rechargable batteries (being pedantic). Lastly and most importantly however the sides have rubber pads by which to grip the mouse. Initially this is very comfortable but they seem to collect dirt rather quickly and I can see them wearing out quicker than I had hoped.
All in all a very solid mouse. I would recomend this to anyone looking for a cheap run of the mill wifi mouse to accompany them and their laptop. This mouse was designed to be taken places and used sporadically would not rekomend for every day use on a desktop, for gaming or any other time intensive computer based activities.