Staltz makes some salient points in his article. The title is needlessly inflammatory, though. Something like "Why Cycle.js/Rx is a Superior Paradigm" would have done the trick. He also explains what he means by "inferior paradigm," and mentions all the virtues of React detailed in this comment thread. I recommend reading the article for interest's sake, even if you find the title offputting.
A note to all owners of Exploring ES6: this is offered to you for free by the author, as it's based on a chapter pulled from that book. He wrote an email update to that effect, but if, like me, you have a few Leanpub purchases it's easy to overlook it. Look out for the latest Exploring ES6 Leanpub update email, you'll find your coupon link there.
Before I spend my hard-earned... does anyone have any experience with the course materials, any short review they'd be willing to offer or any advice as to which package to go for?
There's so much wrong with the Wordpress core that this feels like a superfluous distraction from the real problems that need to be fixed. Even so, it's a big step in the right direction for CMS in general.