use Benchmark;
use strict;
use List::Util qw(first);
my @x = ();
for(0..200) {
   push @x, int(rand(1000));
}
Benchmark::timethese(-2, {
 Grep => sub{my $y  = grep {$_ == 300} @x},
 Util => sub {my $y = first {$_ == 300} @x} });

Benchmark: running Grep, Util for at least 2 CPU seconds...
  Grep:  2 wallclock secs ( 2.05 usr +  0.00 sys =  2.05 CPU) @ 24864.13/s (n=50872)
  Util:  2 wallclock secs ( 2.13 usr +  0.00 sys =  2.13 CPU) @ 7761.41/s (n=16493)