wysiwyg entity id is a string and not in int.

From wysiwyg_entity_info

'entity keys' => array(
  'id' => 'format',
),

While this works, I don't think this is a good idea. If you read the API for hook_entity_info it's clearly states that the entity id key should be numeric.

Other modules might depend on that the entity id is numeric to (as the API says so).

For example the metatags module is affected by this issue.
If you have wysiwyg settings exported with features, and in the same installation profile try to enable metatags, you're gonna be sad as metatags try to insert a string as the entity id and that will not work at all and the installation will fail.