Is resell rights still in demand?

Hi,

I would like to know if resell rights are still popular on
the internet? Can anyone enlighten me?

This is because I have been seeing a lot of other sites
selling resell rights packages that are like an all-in-one-
kind of a business ebook package.

If I am also going into this market as a beginner, which
will be better for a starter? Going niche or also selling
those all-in-one packages?

If it's the latter, what do I need to do in order to
differentiate from the rest of the others who are also in
this line?

Thank you,

Richard