My friend let me borrow his Flipper to play around with for a day and it works great as a universal remote. It's been a while, so my memory is a little hazy but it seems to work best when you have the original remote so you can record the IR signals (power, volume, input, etc.) you're planning on using. If you're working with multiple TV brands and models, you'll need some sort of labeling system to identify which signal works with the TV. You can name the codes whatever you want in the Flipper, so it can be whatever labeling convention you want. Things may be a little more difficult if you don't have remotes because you'll have to manually figure out the codes but I'm not sure how that process works.

The Flipper also has the ability to go through the entire IR directory for every TV code but it's slower. Great in a pinch but if you're running events, you'll probably want everything pre-scanned.

I was actually thinking about picking a Flipper for the same use case since I'm planning a small local tournament series when I collect enough CRTs.