Themeforest is the biggest marketplace for WordPress (and other CMS) themes. However the products are not worth it. We outline the main reasons why here (and recommend going with a Genesis theme if a custom coded theme is not an option).
What’s wrong with Themeforest WordPress themes?
1. They’re bloated
That nice admin interface, along with all the bells and whistles, comes at a cost – the themes can be resource heavy and tough to optimize for performance. I just spent three hours this weekend optimizing a theme that had some issues. I just moved the site to a dedicated server and one page was taking 20 seconds to load.
I proceeded to test the site at both tools.pingdom.com and www.gtmetrix.com to see what was taking so long and saw a laundry list of 60+ files being loaded.
It wasn’t all the theme’s fault – half of it was due to a CodeCanyon plugin (a sister site of Themeforest with, among other code, WordPress plugins). I had to optimize the 17 photos on the page and make some performance adjustments on the server. I also added a caching plugin and minifying plugin. When all was said and done, I got the page load time down to 1-2s – not incredible but way better than before.
Where does the theme come into this? Well – it’s calling files that don’t need to be there. There’s a slider on the home page but not on the problem page, but the files for the slider were still being loaded – what a bunch of crap. All of those bells and whistles comes with a price in the form of extra files for each feature. Not all Themeforest themes are guilty, but if you want one of the fully-featured, everything but the kitchen sink themes, this will definitely be the case.
2. They’re poorly coded
I’m not saying they’re not coded well – they’re just not adhering to WordPress coding standards. These kitchen sink themes add a ton of useful functionality in a very poor manner – they are coded into the theme itself rather than as separate plugins. That means that when you switch themes, you lose these functions and edits and have to recreate them again.
I discovered this when customizing my theme (which I did properly via a child theme) – there were a ton of functions and I realized that changes that I would like to keep in case I change themes would be lost. (In a corollary, guess who just learned to a program simple WordPress plugins?)
That means that you’d be married to the theme or face the unenviable task of recreating your edits in a new theme (and presumably in plugins that you’d have to learn to code). So this fully-featured theme is starting to look like a double-edged sword.
But that’s not the worst of it.
3. You can’t use Themeforest themes for a revenue generating website
Y’all know my thoughts on membership websites by now. I LOVE them. Those and other websites that result in passive recurring income are changing lives for people around the world.
And you can’t build them with a Themeforest theme without paying through the nose. Ladies and gentlemen, I give you the part of the Themeforest License FAQ I’m referring to:

And how much does an Extended License cost? Around US$3000 (vs $30-60 for a Regular License).