Neither is raw. The frames are drawn differently. The I frame means that all the information is in every frame. The B P frames are drawn with partial data that changed from the I frame. So say first frame is an I frame and the next 3 or 4 frames the only thing that changed was the subject moved then only the movement is drawn where the original background I frame is the same.
I use IPB with my Canon 5d mark iii and the quality is very good.
You can still edit footage from the mark ii and mark iii in post. Since video has a flat look I add a little contrast and saturation. I've had good luck with correcting the white balance. There was a discussion of shoot raw, log video recently on this forum. Here