#states does not support integer values, nor OR operator. I only got this to work because this is still a fairly simple use case.

D6 dependent form items

    '#process'       => array('ctools_dependent_process'),
    '#dependency'    => array('radio:' . CDN_STATUS_VARIABLE => array(CDN_TESTING, CDN_ENABLED)),

D7 dependent form items

    // See the ugly typecasting hack to enforce correct behavior!

    '#states' => array(
      'invisible' => array(
        ':input[name="' . CDN_STATUS_VARIABLE . '"]' => array('value' => '' . CDN_DISABLED),
      ),
    ),

form

define('CDN_DISABLED', 0);
define('CDN_TESTING', 1);
define('CDN_ENABLED', 2);

define('CDN_STATUS_VARIABLE', 'cdn_status');
define('CDN_STATS_VARIABLE', 'cdn_stats');


function some_form_function($form, &$form_state) {

  //
  // Only needed in Drupal 6, hurray for #states in Drupal 7!
  ctools_include('dependent');

  $form[CDN_STATUS_VARIABLE] = array(
    '#type' => 'radios',
    '#title' => t('Status'),
    '#required' => TRUE,
    '#options' => array(
      CDN_DISABLED => t('Disabled'),
      CDN_TESTING  => t('Testing mode'),
      CDN_ENABLED  => t('Enabled'),
    ),
    '#default_value' => variable_get(CDN_STATUS_VARIABLE, CDN_DISABLED),
  );

  $form[CDN_STATS_VARIABLE] = array(
    '#type' => 'checkbox',
    '#title' => t('Display statistics'),
    '#return_value'  => CDN_ENABLED,
    '#default_value' => variable_get(CDN_STATS_VARIABLE, CDN_DISABLED),
    //
    // Here either #process and #dependency (D6) or #states (D7).
    //
  );

  return $form;
}