Is there something better than the kakasi library for gojûon collation?

"Better" primarily means accuracy, but I am also interested in any other criteria in which other systems excel. I sampled the Perl binding Text::Kakasi for correctness in an admittedly limited fashion and it works just fine for our needs.

use utf8;
use Encode;
use Text::Kakasi;
use Unicode::Collate;

my $k = Text::Kakasi->new(qw(-iutf8 -outf8 -JH));
my $c = Unicode::Collate->new;

print encode_utf8 $_ for
    map  { $_->[0] }
    sort { $c->cmp($a->[1], $b->[1]) }
    map  { [$_, $k->get($_)] }
    <DATA>;

__DATA__
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