I bought the K360 Colour Collection Limited Edition Wireless Keyboard (the actual design I have is called "purple boulders" and it comes in several different contemporary looks) because I wanted to free up space on a desk which is used for a PC but also for crafting and drawing. My keyboard is white with black keys and a purple design in the top right hand corner. It's smaller than a normal keyboard (Logitech say 20% smaller) and also, being wireless, is easily stowed away when not in use. I paid £15 for the keyboard, which seems to be about an average price, and I'm fairly pleased with it although I wouldn't want to use it for a lot of typing, for reasons I shall explain.
Setting up the keyboard was easy, even for the technically challenged (me). The keyboard comes with a "unifying" USB that you plug in to your computer after automatic set through the downloadable software you are good to go. I also have a compatible wireless mouse on my PC, which runs Windows 7. As the family computer this computer gets a fair bit of use, the keyboard came with two AA batteries which should apparently last 3 years, I haven't owned it that long yet but we have left it turned on (there is a switch on the keyboard) continually and there has been no running down of the batteries.
In terms of day to day use, this keyboard is fine - for my preference the keys are a little too spongy. They are not fully raised keys but the flatter sort you associate with a lap top I suppose, they really are a bit too flat for my preference. You don't need to depress them much to type in, for anyone like me who first learned to type on a typewriter (yes, showing my age I know), this isn't always a great thing. Despite my heavy handed typing the keyboard seems to be cope well and be robust, I don't notice any delays particularly when I am typing. All the usual keys are there, including the number keys, in QWERTY layout, in more or less the normal places. There's a good range of Function Keys, some of which will launch your browser or open email - I can't say I use them over much but the F10 which locks the computer is handy with children around. In use the keyboard is extremely quiet, another plus.
Talking of good points, this Keyboard is extremely light (780g) and does seem quite well built though a bit plasticky and it is undoubtedly quite nice looking for the price you pay. Dimension wise it's only about 15cm deep and 38cm wide and a couple of centimetres thick. I find it fairly uncomfortable to type in if flat on the desk without the two little legs at the back extended, though strangely fine on my lap - you seem to be able to go a fair distance from the USB plug in without the keyboard dropping out - it works on a frequency of 2.4GHZ. I do not know if this is Mac compatible, and nowhere does it say on the supporting documentation so I can not advise if the keyboard is suitable for Mac users.
For me the keyboard is OK, but I wouldn't want to type an essay with it and due to its compact size it does feel a bit squashed in, somehow it's not intuitive to find the space, shift and delete keys. I'm not really sure all the Function Keys which are a big selling point on the packaging are really that necessary, I suppose it depends what you want for a keyboard. For day to day use by someone wishing to surf or run applications this keyboard is fine, if you are looking for something to use for gaming or for lots of typing you may want to look elsewhere. Recommended due to the fact it's cheap, works well, has a 3 year warranty, (hasn't let me down as yet) and seems well built, I'm just not that into it, but it does the job.