Am I missing something or is List::Compare in your context giving you nothing that this code does not? This is probably faster and will use less memory as well.

my @ary1 = ( 1..10 );
my @ary2 = ( 5..15 );
my %h;
$h{$_}++ for ( @ary1, @ary2 );
unique( "Only in ary1", \@ary1, \%h );
unique( "Only in ary2", \@ary2, \%h );
common( "Common to ary1 and ary2", \%h );

sub unique {
    my ( $text, $ary, $hash ) = @_;
    print $text, $/;
    do{ print "$_\n" unless $hash->{$_} == 2} for @$ary;
}

sub common {
    my ( $text, $hash ) = @_;
    print $text, $/;
    do{ print "$_\n" if $hash->{$_} == 2} for keys %$hash
}
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