I don't have experience of these themes directly but I do have a lot of experience with premium (paid for) wordpress themes.
One of the main reasons for choosing a premium theme over a free one is because they are much more customizable. Colours, placements, column numbers, fancy effects on the main page, a site that looks like a full website but integrates a blog but is all based on wordpress - things like that.
They each look daunting at first but generally they have a settings page which you can use to get started on the customizing, so it isn't too bad.
I never believe it though when they say "you can get started with just a few simple clicks".
To achieve the look you are happy with takes a substantial investment of time with lots of trial and error. I even had to get the assistance of someone else to get the current theme on my own website looking mostly the way I am happy with as some things were just over my head, and others had simply vanished and others were reacting really oddly for no reason.
It is satisfying though when you actually get the site looking as you envisioned it and is worth the heartache and hassles involved.
Your site is even bigger than mine so expect a few days of "fun" once you start
