RubyGems is a great packaging library primarily because of its verbose logging information and easy to navigate system architecture. We've dealt with artifactory systems in the past for Java and JavaScript, and RubyGems just makes it a lot easier to handle the packaging and deployment of our reusable libraries. We've noticed in the past that there are times where (if all 200+ teams) are releasing at a similar time that publishing the gems can lag, but that's fairly rare.
RubyGems has strong community support and finding issues to errors is as simple as searching for the error message you're receiving (but usually the error is clear enough without having to bother with that). Honestly, the framework is simple enough that support isn't needed much, but it has been helpful to us in the past when we have needed it.
RubyGems is easier to use and to troubleshoot issues overall. Sometimes when troubleshooting in other systems errors are masked and it takes a trained eye or a lot of time searching through Google trying to find out what it really means. RubyGems is very verbose and allows for quick troubleshooting of any deployment problems.