It's easy to set up in your servers with PHP or any other language that supports it. Very light weight, so you can't do much wrong if you're not doing too much. The performance benefits are huge! There isn't anything I dislike about this product. If you need an efficient cache for something like page load times of things stored by MySQL, then memcache fits that bill perfectly. We use it to store some cached data from our CMS (Drupal) which we don't want to have to fetch every time someone wants to see one of these pages.