Before Polarion Requirement, we used Microsoft Word and SharePoint. 

I have worked with DOORS. I switched to Polarion because I changed my workplace, and that was being used. However, my previous company later switched to Polarion for its enhanced traceability features.

I have experience with Jira and a bit of experience with IBM DOORS.

For small-scale issue or bug tracking, Jira might suffice. But, if you want a single solution to track everything from customer requirements all the way through development and issue tracking, Polarion is the better choice.

We chose Polarion Requirements because it had the best metrics and results in our gap analysis.

I have used IBM Rational DOORS, but I think that it is a bit old school. It is only usable from one perspective.

DOORS is better than this solution with respect to import and export because you don't have as many problems. For example, in this solution, you have to define all of the variable types and enumerations. You don't need to do this in DOORS.

I have experience, from the very basic former engineering requirement, with Excel. It's not really acceptable for the complex items we have. We had another product which was not so good because of the user experience. We have chosen Polarion to make things easier.

We previously used IBM DOORS which isn't exactly the same solution so it's difficult to compare, but for requirements management, it was better.