I finally gave up on all that stuff and got 'Kguard Leaffree Gutter Systems'. I've had them about 3 or 4 years and haven't touched them. I have trees all around my house, mostly ash that drop stuff all year round and not just leaves. Also have a couple honey locust and a few maples.
I think I paid around $4000 back then for the house and the garage but haven't had a lick of problems with them, nor do I get any basement water even through Irene. The leaders are 4" but some they did 6" and the gutters themselves are huge; 5".
Recommend them highly! A friend has had his for 5 to 8 years I think and was who recommended them to me. We're both 100% glad he spent the money.
Not cheap but then so are the ones that don't work plus the yearly cleaning either by you or paying someone. I think in the long run leafree is probably cheaper. No more gutter cleaning for me!
Check them out.
K-Guard Leaf Free Gutter System - The K-Guard System