Doing any of these quals with the Big 4 would be good, doesn't matter too much which. ACA is more widely respected, mainly as that the one the Big 4 trainees do the most. Generally, the course content between the three is much of a muchness. However, typically CIMA is done in industry and ACCA in small accounting firms and the public sector. It's not so much that ACA is a more difficult or more relevant qual but generally ACA candidates are of a higher calibre.