The Costco EasyOn gutter guards are on my 2 story roof. The mesh holes are small and, almost 2 years in, the guards are doing their job.
I installed the Flexxpoint guards from Amazon recently. Comparatively, the material is a lot flimsier (aluminium vs stainless) and the holes are just punched through the metal. I can see how leaf stems would get caught. Leaves are still falling here so I'll get on the ladder (thankfully, it's a 1 story roof) and check them out in a few weeks. The reviews on Amazon, if they can be trusted, claim that pine needles aren't a problem.
Cost: $200 for 100' and 2 full days (had to pre-drill).