Please help me to identify whether I should stick with AUTOLOAD or should I move to Class::Delegator class.

Three thoughts come to mind reading your post:

• The word "should" implies some law, rule or at least good reason for, doing something.

  That reason could be because of your organisation rules: how would a bunch of strangers on the internet know those?

  Or the reason could be efficiency or ease of maintenance of the implementation: trading a single simple subroutine for 150+ subroutines doesn't seem to be a good reason.

  Or perhaps you think that what you have is not OO enough: allowing such academic criteria to override your own assessment is a very bad choice.

• It strikes me that whilst inheritance is way overused, this is actually tailor made for it.

• If your current mechanism works, and doesn't cause you problems, stay with it.

  I might make one change though. Assuming that only one type of connection will be used in any given application:

  sub AUTOLOAD {
      my $connection = $device->getConnection();
      {
          no strict 'refs';
          *{ __PACKAGE__ . '::' . $methodname } = $connect->can( $method
  +name );
      }
      return $connection->$methodName (..); // when called for getVersio
  +n, $methodName will become the "getVersion"
  }
  [download]

  Now, the AUTOLOAD process will only be used the first time a method is called, which could effect a nice performance boost if many calls are made to some methods.