After CA, is it better to do ICAEW or CPA?

If you want to pursue a career in an accountancy firm in the USA, then CPA is a must. You cant get promoted to manager level in a big 4 firm in the USA if you don't have your CPA. If you plan to work in the UK, then the ICAEW is a better choice. I am an ICAEW myself and believe that the topics are more thoroughly tested. The CPA is multiple choice in nature and the examination pattern is quite different. I think you need an American university degree as well to enroll in the CPA, however with ICAEW, you can get a lot of exemptions from your CA, meaning that you will have to write few advanced level papers of ICAEW only before qualifying.