Good advice and welcome.As I said on webhostingtalk, something to make a note of, running fastcgi does not mean you are immune. All someone needs to do is crash your fastcgi processes or webserver. Furthermore, if you run whmcs on a cpanel server with default log processing times and fastcgi, your webserver will restart itself every two hours which makes it predictable.
The underlying technologies are okay. The problem is that SolusVM, WHMCS etc are crapware written by incompetent people who have no business writing software, but get away with it because hosting is now the new kind of lemonade stand. Don't believe me? Look at that shovenose kid -- he launched a KVM VPS company without even knowing how to use KVM.What fun. What will be next? I'm still waiting for the vulnerability in OpenVZ and/or KVM themselves. The main software of this industry is going to shit, anytime now it will be the actual technologies it is based on. $7/mo dedis or bust!