My favorite part about whitesource is that their product is modern. Unlike the competitors, whitesource software is built with modern frameworks and CI platforms in mind. They don't assume you have a server closet or that your entire office runs windows XP :)
I don't really have any complaints. They are growing which means some features are still being built-out. But any time I have had a problem, whitesource has gone the extra mile to provide a work-around or solution. So it's not really a big deal.
Really dig in to whether or not these companies support your stack. We wasted a lot of time looking into companies that knew very well that their software didn't even work with our tech-stack. Their plan was to get you to sign a contract and then bully you into professional services.
With whitesource, run a trial. Take a sample collection of code and scan it. Have them show you the interface and play with the demo. It is such a great experience and you'll find out right in the beginning how well they fit.
Past this, it's very easy to expect a software package like this to do all these tiny little things. But once you get into it, you realize you don't actually care about half of it. So really think about what's important to you in this process and you can save a lot of time.
Also, remember that the folks at whitesource do this for a living. So if you don't understand something, or want to know how other companies handle a certain problem... ask whitesource! They have a great level of experience and could even save you a lot of time and money guiding you to the right answer.
We are trying to make sure we respect all open-source contributors and authors by respecting their licenses. And Whitesource does a great job of helping us do that. Beyond that we get the added benefit of security scans and automated alerts from their system, as well as our CI.
We would eventually like to enact some policies using whitesource so that we can find and correct license issues long before production. I haven't gotten into the policy side of whitesource too much, but it seems pretty straightforward. And I know they plan to continue expanding that.