A React component library gives you pre-built, tested UI blocks so you can stop reinventing buttons and focus on product logic. The real question is not which library to pick but which model fits your situation: do you install a package and stay updated automatically, or do you copy source code into your own repo and own every line? Both approaches are legitimate, and this guide lays out the trade-offs clearly.
Two Models, Different Contracts
Installed libraries (MUI, Ant Design, Chakra UI) ship as npm packages. You import Button from the package, the component renders, and version bumps arrive via npm update. The upside is maintenance offloaded to the library team. The downside is that every pixel is governed by the library's theming API. Overriding deep styles often means fighting specificity or wrapping components with workarounds that accumulate over time.
Copy-paste libraries (shadcn/ui, Radix Themes, Incubator) give you source files you paste directly into your codebase. The component becomes your code the moment it lands. No API to fight. You rename props, delete what you don't need, and the project stays clean. The cost is that you absorb any future bug fixes yourself; they don't arrive automatically.
Neither model is strictly better. A startup that ships fast probably wants copy-paste control. An enterprise team with strict upgrade policies may prefer a versioned package with long-term support guarantees.
Ownership of Code
Ownership is the clearest differentiator. When you npm install @mui/material, you are renting the component. When you paste a HeroCursorMask from Incubator's catalog into src/components/, you own it outright. You can rip out Framer Motion, swap the animation library, change the markup to match your design system's HTML patterns, or delete the component entirely without touching a lock file.
For agencies building client sites, code ownership is often non-negotiable. Clients sometimes need components modified in ways a library's API never anticipated. Copy-paste absorbs that reality without friction.
Theming
Installed libraries usually provide a theme object you configure at the provider level. MUI's createTheme, Chakra's extendTheme. That works well when the design fits the library's mental model. When the design diverges, you end up with a deeply nested override tree that is hard to reason about six months later.
Copy-paste libraries lean on CSS custom properties instead. Incubator sections consume tokens like var(--color-accent) and var(--radius-xl). Swap the preset at the root level, every component responds. There are seven presets in the catalog, from lime-light to noir-bold, and every section in the dark collection or the minimal collection uses the same token system. No prop drilling, no theme provider gymnastics.
The practical outcome: copy-paste libraries tend to produce more predictable designs because the theming surface is smaller and CSS-native.
Accessibility
This is where installed libraries genuinely earn their keep. MUI, Radix, and Headless UI invest heavily in ARIA roles, keyboard navigation, and focus management. Dialogs, comboboxes, date pickers, these are hard to get right, and the established packages have been battle-tested across millions of users.
Copy-paste components vary. shadcn/ui is built on Radix primitives, so it inherits strong accessibility guarantees. Incubator's sections are primarily marketing components (heroes, testimonials, pricing grids), not complex form widgets. Interactive primitives like toggles and modals should still come from a headless library like Radix or Ariakit. For scroll-driven reveals and layout blocks, the accessibility concern is mostly reduced motion and contrast, both manageable with CSS.
Rule of thumb: use a headless accessible package for interactive widgets, use copy-paste for layout and visual sections.
Comparing the Main Options
| Library | Model | Theming | Best for | |---|---|---|---| | MUI | npm package | Theme object | Enterprise apps with dense UI | | shadcn/ui | Copy-paste (Radix) | CSS variables | General-purpose, strong a11y | | Tailwind UI | Copy-paste | Utility classes | Tailwind-first teams | | Aceternity UI | Copy-paste | Framer Motion | Effect-heavy marketing sites | | Incubator | Copy-paste | CSS tokens + 7 presets | Marketing sections, landing pages |
Full comparison pages: Incubator vs shadcn/ui, Incubator vs Tailwind UI, Incubator vs Aceternity UI.
When to Mix Both
Most production projects end up using both models at the same time. A common pattern:
- Radix or shadcn for data tables, dropdowns, dialogs, and form primitives
- Copy-paste sections for the marketing site, landing pages, and visual set-pieces
There is no rule against mixing. What breaks teams is applying one model everywhere out of principle. Use each where it fits.
For the interactive sections in your app shell, install a package with proven accessibility. For the landing page hero, the testimonials carousel, or the stats counter, paste the section, own it, and style it to match your brand without compromise. The scroll-animation and hover-effect collections show the kind of marketing sections where copy-paste wins clearly; none of that is something a theme object configures well.
Practical Checklist
Before choosing a library, answer these:
- Will you need to deviate significantly from the default look? If yes, lean copy-paste.
- Do you have interactive widgets (combobox, date picker, dialog)? If yes, use a headless/accessible package for those.
- Is the team comfortable reading and modifying component source? Copy-paste requires it.
- Do you need automatic security and bug-fix updates without manual changes? Installed package wins.
- Is this a marketing site or app shell? Marketing site: copy-paste sections. App shell with dense UI: installed library.
Closing Thought
The "best" React component library is the one that matches your team's actual workflow and your project's design requirements, not the one with the most GitHub stars. For landing pages and marketing sections, copy-paste gives you design freedom that package APIs rarely can. For complex interactive UI, lean on libraries that have invested years in accessibility. The Incubator catalog covers the marketing side with 449 section variants; browse the full set or go straight to a specific component like the hero cursor mask to see what copy-paste ownership feels like in practice.