It would be because you need to build up to 150 hours anyway before you can start your CPL course. So you have missed out a block anyway by hour building IFR if you would have any sense you would do it at night as well to get night hours. About a 5k plus saving already. IR course is in the 15-18k range.
How much to do a FAA IR and 50 hours spam can time currently in the US? You would also need the MEP and muti engine IR I would have thought.
By doing it the FAA way you will reach 150 hours convert your IR which then gives you 10 hours off the CPL course dropping it to 15 hours. You need 200 hours before you can apply for your CPL.
From the prices of the FL sausage factorys for PPL/MEP/IR and mutli IR I reckon it will undercut the Western European FTO's by 10-15k.