For the FAA IR I'd plump for the King DVDs, and the ASA test prep book is quite useful. I sailed through the exam, and of course there's only 1 exam for the FAA IR, unlike the JAA equivilent which has 7.
As for comparing the effort of the JAA IR course vs. ATPL, what nonsense. The IR course is about 40% of the work involved for the ATPLs.