I needed to replace my old cheap mouse which lasted me a good few years so to replace it I would buy another cheao mouse. I don't see the point in spending more than £10 on a computer mouse, it seems quite steep. It wasn't a necessity I needed one because I use a laptop but I prefer a mouse to the touchpad. I was after an optical one specifically as I tend to use my bedsheets as a mouse mat!
It works as a mouse should. Very comfortable to use, I've had it a good few months now and it hasn't stopped working of anything like that as of yet. It's nice and simple, with the typical right click and left click buttons and a scroll button in the middle. It is very respondive and works very fast. I expect it to last a while despite being so cheap as my last one did, and although the last one wore out rather than broke, it was still usable. I expect this one to wear out quicker than a more expensive model but to be honest for what it's worth I don't mind as much. I'm not fussy when it comes to things like this therefore I won't get rid of it if say the clicker gets stiff or the scroll button stops working.
I'd happily recommend this to anyone who wants a cheap reliable mouse. It works as well as an optical mouse should and I've had no problems with it. Mine cost me £9.99 from a Maplin store outlet but they go for as little as a fiver online. Give it a go if you're looking for a replacement as I did!