i never think a script can affect much on a ppl life but we had a true story here.
I have used MB,Clientexec,WHAP from the day i start my hosting biz; however when i start using WHMCS one and half year ago, never look back to those. WHMCS also have a really good basic support system so i can save my bucks on Supportsuite, and now they are integrated, a perfect match. Before knowing WHMCS, i was looking for an easy to use, easy to edit templates and less load put on server billing system; WHMCS give me all so i always recommend it for everyone i know