I need to decide whether I just want my IR or I want my ATPL in the future. If I decide on the ATPL then its easier to do the ATPL exams straight off or Ill have to do them in the future.
The only theory you need for the issue of the ATPL is CPL + IR, no need for ATPL theory when it comes to helicopters. It's just a smart way of getting CPL + IR theory at the same time. However, you never know if it will change in the future.