it should run a lot faster/be more efficient than the latter

While recursion may make for much simpler code, it will not necessarily make for faster/more efficient code tail recursion is better in this regard. A classic example is calculation of factorials. In my, doubtless horrid, example:

#!perl

use strict;
use warnings;
use diagnostics;

use Benchmark qw(:all);

#print 'looping: ' . looping(10) . "\n";
#print 'recursive: ' . recursive(10) . "\n";

my $count = -5;

cmpthese($count,{
    recursive => sub{&recursive(50)},
    looping => sub{&looping(50)}});

sub recursive
    {

    my $x = shift;

    if($x <= 1) {
        return 1;
    }
    else{
        return $x * recursive($x - 1);
    }
    }

sub looping
    {
    my $x = shift;

    my $y = 1;

    foreach my $z (1 .. $x) {
        $y*=$z;
    }

    return $y;
}
[download]

I got these results:

             Rate recursive   looping
recursive  9228/s        --      -77%
looping   39979/s      333%        --
[download]

Which, if I interpret it correctly, shows the looping sub is quite a bit faster.

Of course, this does not mean that all recursive routines that can be replaced by iterative routines should be; this is likely to be misplaced optimization. There are a great number of cases where the code written with recursion is going to be much simpler, which means that it will globally be better: more reliable, easier to test, easier to understand, quicker to get right.