From what I can see, they do the same thing with the easier to understand map{$_*5} @vals being very, very slightly slower as far as execution time. Doesn't appear to be enough slower to sacrifice the understandability.

#!/usr/bin/perl -w
use strict;

my @values = qw(1 2 3 4 5 6 7 8 9 10 11 12 13 14);

print "Just to show that these do the same\n";
my @vals1 = map($_*5, @values);
print "@vals1\n";
my @vals2 = map{$_*5} @values;
print "@vals2\n";

#prints:
#Just to show that these do the same
#5 10 15 20 25 30 35 40 45 50 55 60 65 70
#5 10 15 20 25 30 35 40 45 50 55 60 65 70

use Benchmark;

timethese (1000000,

 { paren => 
    q{
      my @values = qw(1 2 3 4 5 6 7 8 9 10 11 12 13 14);
      my @vals =  map($_*5, @values);
     },
   block =>
    q{
      my @values = qw(1 2 3 4 5 6 7 8 9 10 11 12 13 14);
      my @vals =  map{$_*5} @values;
     },
  }
);  
 __END__
Just to show that these do the same
 5 10 15 20 25 30 35 40 45 50 55 60 65 70
 5 10 15 20 25 30 35 40 45 50 55 60 65 70
 Benchmark: timing 1000000 iterations of block, paren...
      block: 20 wallclock secs (19.38 usr +  0.00 sys = 19.38 CPU) 
               @ 51612.90/s (n=1000000)
      paren: 20 wallclock secs (19.30 usr +  0.00 sys = 19.30 CPU) 
               @ 51821.53/s (n=1000000)
Just to show that these do the same
5 10 15 20 25 30 35 40 45 50 55 60 65 70
5 10 15 20 25 30 35 40 45 50 55 60 65 70
Benchmark: timing 1000000 iterations of block, paren...
     block: 20 wallclock secs (19.44 usr +  0.00 sys = 19.44 CPU) 
               @ 51445.62/s (n=1000000)
     paren: 20 wallclock secs (19.39 usr +  0.00 sys = 19.39 CPU) 
               @ 51570.32/s (n=1000000)
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