Clarifications on memcache sessions handling for D7

I understand that the memcache session handling for D7 is not yet stable... though looking at https://drupal.org/node/656838 it seems that this mainly has to do with things like mixed http/https sessions, and that the session handler may work fine for a typical use case?

Question 1: what's the worst the can happen when using the memcache session handling? I'm willing to risk a bit of site/session instability, but would not want to risk potentially corrupting my db, for instance...

Question 2: here are the relevant memcache settings in my settings.php... does everything look good here? Specifically, I see from the readme that I need a separate memcache server for the session table and the users table... is it okay to have just three servers then, and put all my cache tables in 'default', while putting 'session' and 'users' in their own dedicated server?

$conf['cache_backends'][] = 'sites/all/modules/memcache/memcache.inc';
$conf['cache_default_class'] = 'MemCacheDrupal';

// DB Cache.
 // Ensure that the special cache_form bin is assigned to non-volatile storage.
$conf['cache_class_cache_form'] = 'DrupalDatabaseCache'; 

// Locking.
$conf['lock_inc'] = 'sites/all/modules/memcache/memcache-lock.inc';

// Stampede protection.
$conf['memcache_stampede_protection'] = TRUE;

// Servers
$conf['memcache_servers'] = array(
  '5.9.54.111:11211' => 'default',
  '5.9.54.111:11212' => 'session',
  '5.9.54.111:11213' => 'users',
);

// Bins
$conf['memcache_bins'] = array(
  'cache'                 =>  'default',
  'cache_admin_menu'      =>  'default',
  'cache_apachesolr'      =>  'default',
  'cache_block'           =>  'default',
  'cache_bml_experiment'  =>  'default',
  'cache_bootstrap'       =>  'default',
  'cache_field'           =>  'default',
  'cache_filter'          =>  'default',
  'cache_image'           =>  'default',
  'cache_libraries'       =>  'default',
  'cache_mailchimp_user'  =>  'default',
  'cache_menu'            =>  'default',
  'cache_path'            =>  'default',
  'cache_rules'           =>  'default',
  'cache_token'           =>  'default',
  'cache_update'          =>  'default',
  'cache_views'           =>  'default',
  'cache_views_data'      =>  'default',
  'session' => 'session',
  'users' => 'users',
);