A standard Blu-ray release typically offers much higher quality than a 700MB 720p file, usually in 1080p resolution with a much larger file size (often 40-60 GB or more for the full HD version). However, if you're looking for a more portable or space-efficient copy, a 720p version could be a compromise.
Squeezing a high-definition, two-hour movie into 700 megabytes required incredible software optimization. Encode groups utilized cutting-edge codecs to achieve this feat: the forbidden kingdom 2008 bluray 720p 700mb fixed