Maybe Jags are more sopisticated? al ours have a differential pressure sensor on them and this is a source of problems as well!! on 3 litre XFs it lives above the gearbox it creates faults or the wiring to it breaks! To be honest if driven like they should be with correct very expensive oil regular runs we dont get many problems the trouble is people forget do 3 weeks in town and bang DPF light on and restricted performance up!! its a bugger
Look at the pricetag of the cars...& year of production. Think thats my best answer to your sophistication ;-) As stated, its a pressure-sensor in front, not a differential (over the filter) on alfa 159-series.
Im mostly doing 200 Km runs in mine, so thats not a factor. I dont expect any real increase in performance, some people report less lag in turbo-responce, but belive its due to "knowing-its-been done" factor. I can see that tuners get 5-10 more BHP out of it, if DPF is removed, but with approx 240 already, 10 extra wont be that noticeable.
Been to an Alfa-garage, where they are sick & tired of all the problems, as you describe, with clogged up filters & EGR+inlet manifolds completely shut of by soot...Its just so wrong when the sales-people forget to tell people that modern diesels just dont work in town alone, must cost them a fortune in hours & spareparts...& customers fleeing from the brand (no matter which brand, EGR & DPF are problem and present in all new cars)
Primary reason for me to remove DPF, is so i can stop using the insanely expensive low-ash type of oil....I replace every 15.000 Km/ (9000 Miles), so will put me on ½ budget on oilside, never need to buy new DPF, & with blanked off EGR, she seems to do a bit more per gallon too...The extra fuel for regens are so little extra that its not really worth mentioning..But nice to know that my oil wont get thinned out with diesel too....Which alltogether should increase the life of the Engine, and chances off a troublefree relation with that part of the car many years ahead :-)
But...Still only excuses when comming to the law-side of it, which is what the garage faces if getting caught in MOT´ing a car like mine, or even perform the modification.
(edited due to a few beeing non-english mistakes ;-) )