[jasim]

I don't know who downvoted you or why, but yes - performance could be a problem as you pointed out. I prefer the React model simply because it is more programmer friendly. I would hope that performance is something that can be fixed, or at least the 80-20 rule will come to help.

[daliwali]

Most JS server-side rendering never approaches anywhere near string concatenation performance, and I've tried. Whatever abstraction you use has to resemble string concatenation without doing much else, and it's really, really hard to not do much else. That's why embedded JS templates (EJS) is so fast, it just concatenates strings with some logic built-in to the template.