Since DVDs are ~5mbps mpeg2, no, no it isn't. 5 mbps h264 is dramatically better.

Now, when compared to blu-ray... That's different. Very, very different.

h264 is (generously) about 2x as efficient as MPEG-2, granted, but you're smearing those 5mbps across 6x as many pixels.

I would take crisp 480p over a gooey, artifact-softened 1080p for most content.