Over the years there have been many opinions on what CMS offers the best search engine results for your web site. Many of these opinions deserve some consideration, but the bottom line is...
Search engines don't care what you use for your web site !

That's right, unless you are using a system that obscures your site content, you're good. Yay ! Now here is the bad news.... Content is King. Talk to anybody who is working on organic search engine rankings and they will confirm the mantra, Content is King.