Using the SnapX with an iMac for Target Display Mode

Right, so I have a very niche set up going on here, but here goes.

I have a Late 2009 iMac being used as a display for a PC via Target Display Mode. Now, the problem is, when I'm using my iMac for work, I've noticed I'm beginning to run out of space. If I were to buy a Cinema Display obviously the only Mini DisplayPort on the iMac would be used, and I'm not one for constantly switching cables at the back of my iMac. Since the iMac will be in the centre of my desk I want the PC to output to it. Would it be possible for me to use a switcher like the SnapX to switch the MDP on my iMac between the PC and the C.D? Or perhaps you could suggest another set up.

If the above is completely impossible, then I'd settle for using the C.D as the display for my PC. Since the C.D isn't like normal monitors accepting multiple inputs (which can I say is ridiculous considering the price you pay), again I'd have to use something like the SnapX (except this time it's being used the way it's supposed to). So the follow up question would be, and I know the SnapX works with 2 macs, can it work with a PC?

Again, if the 2nd option is impossible, should I just buy a Dell Ultra Sharp or the like?

Regards,

Mike.