I do my CPL first as it is easier. If as everybody says the IR is tough, when am I likely to find out? 5 hrs in? 15hrs? Nope, I reckon 170A time is when it sinks home. If I decide to bail out then, then that is 6K less wasted on CPL. Am I likely to have trouble with the CPL to save my money on the IR? Um...nope.
Yeah thats a good point in theory, the trouble is people dont bail out unless they completely run out of money. Its human nature to keep on striving, most people are 'soooo close to passing, just a few more hours should do it', or 'I've come this far I cant give up now'.
Running out of money is a real danger, if you fail or partial it's nearly £500 for a partial re-test, nearly £700 for a full re-test, plus aircraft hire, re-training requirements, new 170a etc. But can you put your hand on your heart and say you would sack it after already paying 12 grand?
Apart from the the twin/complex handling aspects the IMC seems to cover the vast majority fo the IR syllabus.
It looks like it on paper doesn't it? but maybe ask yourself why it's a 55 hour course as apposed to 15?
Anyway, good luck whichever way you decide to go
M