I made the transition from Bootstrap to Semantic a few months ago on a medium sized project. There are some “gotchas” with some of their components and how they interact with reactive data (and data that may not be available right away), but overall I’ve found it to be a very enjoyable framework to work with, and with a decent amount of community behind it.
There are a few quirky things to look out for, like the fact that SUI uses class name order and meteor strips dup classes, or that you will need to call
$('.ui.modal').modal('refresh') after populating a modal with dynamic content that changes the modal size.
If I were to do things over again, I think I’d take a week or two and build out the components I know I’m going to be needing first, to understand them in an isolated environment. A good example of this learning experience for me was understanding how to pre-populate a select dropdown without firing the
change event for the select.
There are actually quite a few patterns I’ve found helpful in working through Blaze+SUI, I just haven’t had the downtime to really document them out. Feel free to DM me though if you run into specific things!