What are your project settings?
Premier Pro doesn’t have a preset for H.264 Quicktimes.
You might try using one of the XDCAM or DCVProHD presets.
If you import the footage into a NTSC projects – it will downconvert the footage to DV and if you try to blow that up to HD it will look ugly.
But this is all guessing without knowing more about what you did.
Interesting camera though.