When comparing Amber vs CanJS, the Slant community recommends CanJS for most people. In the question“What are the best JavaScript libraries for building a UI?” CanJS is ranked 12th while Amber is ranked 19th. The most important reason people chose CanJS is:
CanJS supports all modern browsers and IE9+.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Includes an IDE
Amber includes an integrated development environment with a class browser, workspace, transcript, object inspector and debugger.
Pro Smalltalk is a simple, elegant, and powerful language
Pro One-to-one JS equivalent
Amber is written in itself, including the parser and compiler, and compiles into efficient JavaScript, mapping one-to-one with the JS equivalent.
Pro Great browser support
CanJS supports all modern browsers and IE9+.
Pro CanJS can be used with any other library
CanJS is a collection of individual libraries, each separately available as npm packages. It's easy to use just what you need.
Pro Real time support
CanJS's model layer (can-connect), support real-time updates to lists without adding any additional code.
Cons
Con Very few learning resources
There are very little learning resources for Amber outside the official documentation. Which may not be enough for beginners, especially people that don't have much experience in programming.