Basically they are schite construction and as most folks are afraid that the filter will fall off they horse it up as tight as they can
When it actually is only hand tight and then plus 3/4 turn (AS A ROUGH GUIDE!)
both filters that i had to cut out of peoples bikes were Hi Flo every other one I have been able to get out (including those stupid K&N ones with the nut spotted on!! WTF???)
Both of the hi flo one spun between the flat metal bit at the base and the outer can, even steppers screws and sandpaper were useless and I had to cut the tin away to get at the metal plate and devise another method of spinning it
Mahle Knecht and BMW are all good and have never caused any problems even with the wee man who horsed his up so tight it buckled that threaded metal plate