Best Paid/Free Courses you've taken

What are some of the best courses you've taken (paid / not paid)?

2 I am considering now:

Masterclass.com (assorted/hobby knowledge?) -- has anyone tried it? How do you like it?
Goodui.org (UI/design) -- I like their content, think it might be worth it to take a deeper look.

Demandcurve.com (growth/marketing) -- I just signed up for their self-service course ($499/month, but they had 50% off for the first month) -- will test it out for a month and see how the value is. $499/month is pretty steep, but I've used the julian.com website quite a bit in the past, and have gotten good value out of their newsletter tips.

I thought $249 to see how it is for a month is fair, and even if it isn't, I won't feel too bad.

Here are some of my recommendations.

I've really liked:

rallycoding.com (node/react/graphql)
$10 per course, great value, good teacher with project-based courses to learn node/react/graphql. Not sure if they're still up to date, but a great way to learn IME. I'm not a huge fan of udemy, but some of their courses are really great value.

https://www.hackingwithswift.com/ (Swift)
Good way to learn swift.

https://www.udemy.com/share/101WsWCEMceVxVQw==/ (iOS/Swift)
This Udemy course was also really good, but you could just follow the Stanford iOS classes on iTunes U or whatever it was called (does it still exist?). I think I paid $13 for it, which is amazing value imo.

refactoringUI.com (UI/Design)
Not a course, but a book. Well worth the price, IMO. Lots of small tips and examples that really clarify your UI design. Wasn't going to buy the book, but I've been using tailwindCSS and really like their free material, so thought it was fair.

Color palettes are great, components are passable. Haven't watched the videos.

Good, but might not recommend:

coursera.org (Deep Learning)
Pretty good course, a little dry and I don't think I learned a whole lot (a lot of memory stuff that was tested in the quizzes/projects -- but I guess it's more of a primer than an in-depth course). You could definitely implement existing deep learning algorithms using this course, but I don't know if it would be all that useful on it's own.

I've heard good things about fast.ai, but maybe it's the same?

Udacity free courses
Their free courses can be pretty good. Hit and miss, IME.

Not a huge fan of:

Udacity Paid Courses
I find most of the paid courses are not that well designed. I think I've started 3 and ended up using different websites to learn the material instead.