This is a fantastic Joomla extension to sell any type of files. It does what it promises and you don't have to be an expert to make it work. Setup is simple and you quickly get what you need. You can also offer files for free and monitor statistics. It also supports "pending" payments - you decide whether to wait for the money or to allow immediate download.
Of course, there is still a room for improvements but most essential requirements are already implemented. The support is responsive and finally, the extension is fairly priced.
A perfect component for paid downloads.