This seems about right. Great article! Almost every client of mine who complained about performance issues were still on PHP 5.2 and almost never opcode caching unless its pre-configured from cPanel or web host. I'm guilty of still using PHP 5.3 on my own server, I did upgrade to 5.4 but found that PHP 5.3 with eAccelerator to be extremely fast and since cPanel does not support 5.4 with eAccelerator it meant I had to manually recompile eAccelerator after every easyapache update. Could use APC with 5.4 but have found to be the same speed as 5.3 with eAccelerator. Now built in opcode caching for 5.5 will be faster than both 5.3 and 5.4 in most cases correct?