Ease of use of defect management software.

Other people's questions, want to understand each bug platform (http://bbs.51testing.com/viewthread.php?tid=474265), reply to the following content.

You say usability is for testing or development. Ease of use see usage habits, most defect management software operations are similar, and not complex to the need to specifically say the degree of usability. Only the ClearQuest feel is easiest for the user, but the configured testers are the most complex. Commercial software is generally better than open source, Jira, QC (TD), CQ ..., where's the money? For example Jira distribution, CQ of the super powerful customization.
Open source defect management software, feel mantis is very powerful, but need to see the use of manual and source code, which really left a lot of interface to people, as long as a little understanding of PHP, read the document, a lot of features can be modified out of their own.
Other such as Bugfree, Zen, Redmine, etc., is not a pure defect management, mixed with requirements, use cases and other content, pure defect management, a little weak.
Bugzilla is Perl, many years ago installed, anyway only remember it is difficult to install, need to update a lot of things online, our unit can not access the Internet, not recently tried, will not have a big mouth.