After googling this for a couple of hours, it seems that Dumpxs should be used in situations where you have massive amounts of data to process. It's more graphically concise than Dumper. I threw together two examples---they don't use massive amounts of data:). The 1st script uses Dumper, and the 2nd script uses Dumpxs. You'll notice the difference:

#!/usr/bin/perl

use strict;
use warnings;
use Devel::DumpSizes qw/dump_sizes/;
use Data::Dumper;

my $path = system('find /usr/bin/*pdf');
&Devel::DumpSizes::dump_sizes($path);
my $d = Data::Dumper->new([$path]);
print Dumper $d;
[download]

#!/usr/bin/perl

use strict;
use warnings;
use Devel::DumpSizes qw/dump_sizes/;
use Data::Dumper;

my $path = system('find /usr/bin/*pdf');
&Devel::DumpSizes::dump_sizes($path);
my $d = Data::Dumper->new([$path]);
print $d->Dumpxs;
[download]