To fly as captain of an airliner you need an ATPL.
Do the ATPL exams and the CPL/IR flight tests and you meet all the requirements of an ATPL apart from the experience.
You are saved doing the CPL/IR ground exams if you have the ATPL ground exams passed.
You end up with the same from both, there again you end up with the same from all of the "modular" schools too for half the price.
Hope this helps
Dibs