The IR(R) is recognised in France. The full IR is more for airways flying, mixing it with the airliners above 10,000 feet and doing it almost whatever the weather. The IR(R) is more of a basic IR that is supposed to teach you how to safely get yourself on the ground should you fly into IMC. Its still very comprehensive and will certainly improve your flying and is pitched at the right level for cross channel PPLs.
I would think there are almost no PPLs that are not pursuing an ATPL that have a full IR. Of those that do, they'll be flying their own Learjets and piston twins or turbines. The number of single engine piston pleasure drivers with one is probably close to zero in the UK.