Question about DV and MJPEG

[OtakuMegane]

Ok, after reading the guides about half a dozen times each and much extra research, I finally have what I need except one thing. First, I'm on a Mac, so MJPEG and DV are the best options for editing codecs I have(don't have the space for the component video codec unfortunately). Now, I've heard many people saying DV is better than MJPEG, and I can see why. It does some kind of blurring as it compresses, hence less visible artifacts and a bit more efficient compression. Rip a DVD with text recorded in the video itself and you'll see it quite well. MJPEG doesn't do anything like that.

My question is, which order is better:
- DV w/blurring at the beginning, edit that video, then do final compression to MPEG-1 or 2 without any extra blur-type processing
- MJPEG straight from DVD, edit, apply light blur/etc. to smooth out artifacts, then compress

Either codec is fine with me(though I feel more familiar with JPEG codecs), just want to know if there is much quality difference between the two editing orders, or if it doesn't really matter.