Yes, the customers and employees passwords are kept in the Premium version.
You can see all the features on http://www.fredericgilles.net/fg-prestashop-to-woocommerce/
Hello,
I don’t understand because I used premium version to migrate prestashop to magento and all user can’t login, they ask new password.
So password are not kept
@eclectic77
The passwords are kept with the Premium version.
To import the right passwords, you must fill in the “Cookie key” field.
It must contain the exact cookie key that you can find in the PrestaShop file settings.inc.php (PrestaShop 1.5+) or in the PrestaShop Preferences > Database tab (PrestaShop 1.4)