React UI component libraries / frameworks

react-bootstrap

Good:

Bootstrap benefits
Existing bootstrap templates

Bad:

Bootstrap cons
Project is in a weird state. No major 1 release and the work to migrate for bootstrap 4 has been on for over a year

material-ui

Good:

Very popular
Can be themed
Google look

Bad:

Google look

rmwc

Good:

Wrapsofficial Google components underneath
Google look

Bad:

Google look
Not that mature and popular
Wrapping underlying JS stuff might be a bit hacky compared to "native" react lib

reactstrap

Good:

Bootstrap
Project looking good, and uses v4. Good looking code.
Does not wrap underlying bootstrap js

Bad:

Bootstrap

Fabric

Good:

Microsoft look
Solid components, good guidelines for using them
Good documentation

Bad:

Microsoft look

ant.design

Good:

Looks really good, especially transitions and animations. UX has been designed well, guide lines
Very popular

Bad:

Sometimes Github issues are in Chinise
Components are not always good fit for mobile

Grommet

Good:

Full blown design system
Components, templates, and guidelines

Bad:

Visual look not perfect