I have been usinig "NoToil" air filter oil for a while now and have noticed on both bikes the air filters have "broken down"

I was quite surprised while cleaning the filter on my 800gs there was a couple of spots on the unifilter pods where they looked a bit "frail". Whilst inspecting the filters they literally broke apart in a couple of places. Same thing happened on my WR450 (spare) air filters. I have always cleaned the filter after every ride with the recommended cleaner.
After talking to a couple of people at some local dealers they said they would steer clear of No Toil for that reason (even though they still had it on the shelf) and use mineral air filter oil.
Any thoughts on the best stuff to use, I have just purchased new filters for both bikes and will not use No Toil again .
Linz
