Gravity Forms Dynamic Checkbox Prices

//Adds a filter to forms
add_filter("gform_pre_render", add_dynamic_options);
//add_filter("gform_admin_pre_render", add_dynamic_options); // Run code in the admin section (not needed)

function add_dynamic_options($form){
    foreach($form["fields"] as &$field){
        // replace prices on fields with dynamic_options class
        if($field["cssClass"] == 'dynamic_options'){
             foreach($field['choices'] as $chID => $choice) {
                // get the value
                $dynVal     = $choice['value'];
                $realVal    = @$_GET[$dynVal]; // actual value can be retrieved from wherever but I use $_GET variables
                if($realVal!='') {
                    $field['choices'][$chID]['value'] = $field['choices'][$chID]['text']; // Set value as the Title - makes it easier to understand later
                    $field['choices'][$chID]['price'] = $realVal;
                }
            }
        }
    }
    return $form;
}