I wondered whether using abs to get absolute value then making one comparison rather than two would be quicker. Apparently not.

use strict;
use warnings;

use Benchmark qw{ cmpthese };

my @data =
   map { rand( 20 ) * ( 1, -1 )[ int rand 2 ] }
   1 .. 1e6;

cmpthese(
   -10,
   {
       abs => sub { my @arr = grep { abs $_ <= 10 } @data },
       two => sub { my @arr = grep { $_ >= -10 and $_ <= 10 } @data },
   }
   );
[download]

      Rate abs two
abs 5.11/s  -- -9%
two 5.62/s 10%  --
[download]