hmm - I like my ITG - It 'looks' as though it would be free-er flowing than the JR and is very tough plus you can wash it, reoil and throw it back in.
Is the JR not paper based? Do they eventually die? - Not sure.
Quote from JR Filter website: JR Airfilters are manufactured with 4 layers of chirurgical cotton, which are hold together by 2 layers of steel wire mesh. To prevent rust, they are galvanized and covered with plastic which give a double security.
Already at the factory we charge the filter with a special oil of blue colour. This oil is an very important element of the filter. Due to the construction, the material and the oil, the dust which is in the air, is retained outside of the filter and serve as supplementary filter element. That’s why those filters can be used without cleaning in some case over 150000 Kilometres.
No more filter change is necessary. 40% more air is passing through thoses filters. The filter capacity is more than 97.5%. The great car manufacturers demands only a filtration of 96%. JR Filters grant lifetime guaranty to the first owner. They are washable, that means they are always reuseable. The power will be increased and the fuel consumption reduced, at the same way of driving.
Tests in the UK with heavy duty trucks proved, that all trucks equipped with those kind of filter, had between 7.5 and 8% less consumption.
Quote from ITG website: The technology of 'Reticulated Polyester Foam' allows us greater flexibility in design and performance than paper or other filter technologies. This gives us the opportunity to make an air filter to your exact specification. ITG were perhaps the first to make a truly durable and high performance foam based production air filter. This heritage has stood us in good stead throughout the competition world for nearly a generation.
By using various thicknesses of finer or coarser foams, our designers can vary the above factors to achieve the optimum for each application. It has been shown that small quantities of dust particles smaller than 10 microns have no significant effect on engine wear, so the materials used in our range of filters have been carefully selected to give good air flow capacity, excellent load-up tolerance, and high efficiency whilst avoiding unnecessary extraction. Where high dust flow rates are possible, we tailor the filters to arrest even the slightest dust
Interesting on the MAF sensor - I'll keep an eye out for that and not use too much oil.
As for cleaning the ITG - the foam comes right off the mesh and it takes about 10mins (handwash) plus drying and re-oiling.
Having never seen a JR filter, I can't comment but it sounds good.