I'm a web developer that is new to WordPress and wanted to hit the ground running so I purchased Builder (I retired my clunky custom-built CMS). At first I had a few issues (like refresh not working) but the more I use it and the more I learn about WordPress the more I like what Builder offers. Support has been very patient with me.

Kevin - I thought it was pretty clear that Builder themes were required for Builder, although I have to admit that the 9 existing themes aren't super. This really doesn't matter because the power of Builder is building your own customized layouts to meet client needs. With the price as low as it is one site more than pays for the license - I think you should take another look and you might find that what you own was well worth the money.

I bought the iThemes plugin package as well - worth it just for BackupBuddy I'd say.