Road conditions and surroundings can make a large difference. Here in Ohio, we have cottonwood, pollen and salt residue in the springtime plus seemingly endless road construction. Most street owners we know clean their filters at the beginning of the riding season, and maybe once again of the conditions are exceptionally harsh. For those who ride continually, or in very harsh conditions we suggest cleaning every 1200 Miles (2K km) The good news is that cleaning a Sprint Filter is an easy/quick task. Just a shot of compressed air (From clean to dirty direction to blow debris out of the filter) does the job and you can get back to riding.
Here is some information on a long-term test with over 5K miles on a Sprint Filter P08: http://blog.brocksperformance.com/sprint-filter-p08-long-term-test-kawasaki-zx-10r-2016/