In order to avoid too many files. As i said,  there are some links link to
other sub-sites that i don't want.(you know all the forums do this). I think
if I max depth limit, it will just download the more shallow depth of the
sub-sites I do not want. If I leave the defaul, it will download everything.
In my case, if  I leave the defaul, will it take less time? By the way, does"
the defaul" mean leave the option blank? no level number?