SiteSpinner Pro is the elite software of Virtual Mechanics. It sports the most features and of course is the most expensive, coming in at $97.00. I'm all about free and or cheap but I did recently purchase the pro version at a much discounted price because of my past purchase of SiteSpinner.
I've yet to use it, so I can't attest to its usability. The main reason for the purchase was to have a site builder with an easier to use responsive design capability. If you remember from from other writings, responsive design is a must for SEO and Google search placement.
RVSitebuilder Pro has by far the easiest responsive design as it is only the tick of a box to put it into effect but SiteSpinner Pro claims to have an easy go of it as well, so I'll just have to wait and see.

SiteSpinner is something I've used quite extensively in the past. I created a rather large site (40-50 pages) for an organization I was involved with. If you stick to the basics of web design, the learning curve is not all that steep but it can get as complex as you want.
Even though I am using RVSitebuilder exclusively right now, I am always drawn back to this software, hence my recent purchase of the pro version. Very professional web sites can be produced with SiteSpinner, the only real drawback is it does not have responsive design capabilities, as that is reserved for the pro edition only.
The price for SiteSpinner 100% free.