On IF and the levels in IM:
Having a surprise round with the wizard inside of an AMF is rather unlikely. Even non-TO wizards usually wear pointy, cloth hats that are in fact a cone of lead larger than themselves, which they have used Shrink Item on.
Thus, if the Wizard begins in your AMF, he is immediately inside of a lead cone, enjoying total concealment, with a contingent spell (If my hat becomes a large metal cone...) going off.

I just don't see it being likely that you'll be able to IF him.

Still, it's a great feature for if you have some other means of catching him by surprise.