You were absolutely right, please accept my most sincere appologies... I hear K&N and I don't really think on oil filters... And as you use oil on the air filter, thus my confusion, apologies...
30 years ago there were people saying that hiflofiltro were blocking and causing engine failures, never saw any one failing, changed a lot of them on several SR250, but got a lot of thoughts about it every time I was holding one of them on my hands...
I would be more worried by the fact that K&N does not like the standard housing, and you need a different tool to remove and fit it...
I have only changed oil filter once on the Fazer (lately), and I reckon that the price from Yamaha to any other is totally marginal once you do the change yourself...
£6 for an hiflofiltro, and £17 for a Yamaha, £14 for the K&N
Taking into account that the K&N price is similar to the Yamaha, why bothering? I would understand considering the cheaper one instead, and then start complaining about breakages...
Also I totally understand the "performance" for an air filter, as it is inline with how the machine works, but these days, and with the bike at this age, I am much worried that the oil pipe in front of the barrels does not fall apart by rust, much more than a freshly bought oil filter, no matter the brand...
I will doubt that any decent factory (any one with a name on the filter, specially those with a lot of years doing them) could make faulty filters these days... I will consider instead how people will fit the filter, it may happen that those "performance" filters have a slightly smaller rubber (just making thoughts on my mind), and if you don't put oil properly on all the surface they end up breaking the seal sooner than expected..., or that the fact that it requires a different tool, may make people not tighten it properly...
Again, please accept my appologies for the confusion...