@Blacklightning13: M'gann would at least be able to get far enough into his head to know that is what he's planning and take appropriate defensive actions. And other white martians have displayed blitzing and combat speed greater than Supergirl and at least as good as Superman. I don't see why M'gann would be any different.
Even if she does get inside his head there is nothing she can do against an IMP.
go intangible. and has Supes ever performed a IMP?
I think he has but I don't remember. But anyway if you can go faster then light then you can do an IMP.
In theory, but to my knowledge Flash if the only one that's been described as performing it.. MM has gone FTL too btw (Edit: well at least other martians have)
Yeah but the difference is that Superman can get to light speed within a minutes. While MM can probably do it.