PHP accelerators

Comparisons of various accelerators:

1. http://itst.net/wp-content/uploads/2006/10/PHP%20Bytecode%20Cacher%20Review.html
2. http://blog.digitalstruct.com/2007/12/23/php-accelerators-apc-vs-zend-vs-xcache-with-zend-framework/

Users reviews:

1. http://agilewebmasters.com/robert/what-is-the-best-php-accelerator-to-use/
2. http://stackoverflow.com/questions/721600/php-accelerator-review