Difference between IELTS and TOEFL:
* TOEFL is conducted by ETS, a non profit organization in US, IELTS is jointly managed by the British Council, University of Cambridge and IELTS Australia.
* While IELTS scores are valid in US also, Universities in US and Canada prefer TOEFL over IELTS.
* One of the biggest differences between IELTS and TOEFL is that while IELTS assesses proficiency in British English, TOEFL measures proficiency in US English.
* Though both assess abilities in reading, writing, speaking and listening, formats of the two tests are quite different.
* TOEFL has more multiple choice questions while in IELTS candidates have to copy words after listening to a conversation.
I think IELTS is more valuable then TOEFL for MBA in US.