What are some alternatives?
When comparing JDownloader and qBittorrent, you can also consider the following products
Free Download Manager - It is a powerful modern download accelerator and organizer for Windows and Mac.
Transmission - Transmission has the features you expect in a BitTorrent client: encryption, a web-based interface...
Internet Download Manager - Internet Download Manager is an application that is designed to make downloading, organizing and storing your files a whole lot easier. If you are like many people, you might download a lot of files from the internet on a daily basis.
Deluge - Deluge is a full-featured BitTorrent client for Linux, Unix and Windows.
DownThemAll - DownThemAll is a free extension for Firefox that is designed to allow you to download multiple links or files on a page without having to click each link.
BitTorrent - BitTorrent is a peer-to-peer program developed by Bram Cohen and BitTorrent, Inc.