FlexJS is actually beyond PoC at this point, but the docs are proving to be slow to catch up. The contributors have been discussing doc improvements on the mail

FlexJS is actually beyond PoC at this point, but the docs are proving to be slow to catch up. The contributors have been discussing doc improvements on the mailing list recently, and I think once the content is better fleshed out, the perception of the project's maturity will be way different. You should check it out, ask questions on the mailing list, and point out what seems especially missing in the docs.