Nah, it's a legitimate point I suppose but really the size of the filtering medium is a bit of a non issue. If you change the filter every 10,000 kms like you're supposed to it'll never load up unless there is major destruction going on. By then filter size would be the least of your problems.
Lucian. The bearing damage is evidentiary of oil starvation rather than particulate damage, (Pics on the Ghetto.) When I pulled the sump spacer I found a small piece of gasket around the oil pick-up gallery for the lubrication oil pump was missing. Now I don't think I've ever had my sump spacer off before so my guess is that it was damaged on assembly eight years ago at the factory. I assume that for the last eight years oil pick-up has been somewhat compromised which may of contributed to some of the awful racket my bike has always made. Why it should choose to begin to fail catastrophically just after rollerization I don't know but mine is the second bike with a similar issue I've had in two months. Mark S's bike also did its big ends just after it was rollerised but it seemed to have had a very hard life and suffered considerable neglect while in the care of its original owner.
To answer the question though, yes, I had back-flushed the cooler and checked oil pressure after the rollerization. Didn't get the engine really hot though which probably would of shown a substantial pressure drop due to the bad gasket.
Do you know which kit your bike requires? If not I can give you the details of how to identify what engine you have.
Pete