I use Xaraya CMS. It’s probably the best featured and flexible CMS, although it is quite difficult to start with. It’s the 3rd year now using Xaraya and everyday I learn something new.
I think all is search engine friendly with it, and it’s flexible enough to do anything. Updating the site is easier than using any simple html with an editor. For a large website, I think a CMS is the way to go. For a 6-10 page website or less, maybe going with a CMS is only the best way, if you know well the CMS you’re using, otherwise you will spend 99% of your time understanding the CMS instead of developing content.
If you want to take a look at Xaraya running, look at my website sharpgambler.com