I can't say about the Qidi or the Trinus, but I disagree with curious about building a kit. The Prusa comes with everything necessary to construct it, although you should have internet access to view the most recent version of the construction manual. The assembly instructions are superb and the print quality is equally good.

Joe Prusa is also well known for good support via email. If you have the slightest problem or question, you can send an email and get a prompt response. During the construction of the recently purchased kit, one of the staff had a question that was even more easily located by searching using the terms "genuine Prusa i3" followed by the question phrase.

If you purchase a Prusa kit, you will also gain much experience and understanding of the construction, making life easier should minor issues arise. Save US$200 and get a bit of an education as well.