It might be true that gutters will not clog but what about the micro-screens? Dirt, pollen and whatever small particles clog the screens and now instead of just cleaning out your gutters you have to scrape the *** off the top and then soak the screens/scrub with a brush and then wash off.
So now a job that maybe might have taken 2 hrs to do takes days.
Also watch on how they are installed. Mine have been up 4 yrs now and rain water has back up ,due to flashing that was installed improperly, under the shingles and now my roof is leaking .
Product or Service Mentioned: Leaffilter North Filter.