Mine is still going well.
Not perfectly, but good enough and better than the bits and pieces I used to have.
Only neg comments I currently have are the filters always come loose. Never fall out, just don't seem to sit nicely in their allotted slots.
Also the filter retaining clips have started to show some surface rusting.
rusting clips won't be a problem, just don't have any rustoleum type paint at hand for now, but will do it.
Just the filter stuff coming loose ... it's more annoying than a problem.
I have a 30min commute, all highway(about 40-ish klms). I leave with them in place, I get there .... and one or two(the same recalcitrants!) have worked loose.
Not a problem at all, if you don't pop the bonnet, but as soon as you pop the bonnet up, there they are ... trying to escape again. And as I paid (pretty much) bugger all for them ... I still demand they stay in their designated positions! 
(current solution is to not open the bonnet)
Arthur.
All these discos are giving me a heart attack!
'99 D1 300Tdi Auto ( now sold :( )
'03 D2 Td5 Auto
'03 D2a Td5 Auto
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