Desktop USB switching

ATM I have two keyboards and mice on my desk. One pair for the G4 and one pair for the Macbook. The monitor allows me to switch between two inputs, so thats easy, but I had thought I’d be stuck with two sets of input devices. However, whilst looking at USB hubs in Maplin on Saturday I came across this little device, http://www.acrox.com.tw/productdetial_specifications.asp?id=124 which lets you switch 4 devices between 2 computers. Now I know USB is hot pluggable, but I can’t help but wonder how this will cope in real life. I’m thinking now that for 25quid I should just have bought it, but I figured I could get one for less that 25quid online, seemingly not though since I can only find this device, or anything like it, at Maplin.