Depending on the country that produced the
bootleg, there may be MAJOR scenes deleted from
the anime. A good example is the Tenchi Muyo
DVD's. Due to the origin country's restrictions
on nudity, every single scene with anything
slightly resembling bare flesh was simple left
out. No attempt was made to keep the plot intact.
When a questionable scene came up, the action
simply jumped ahead until it was over, making the
story disjointed and confusing.
I'm glad I only paid about $15 for the OVA
VCD bootleg. It was worth it as an experiment,
but I'll definitely buy the licensed DVD's