Why the seam matters more here
Most gutter failures we get called out for do not start with the hangers pulling loose. They start at a seam, a joint between two factory-length pieces that was caulked once and never looked at again. In a climate with a real freeze and thaw cycle, water sitting in that seam expands when it freezes and works the joint open a little more each winter. After enough winters the seam splits and the gutter drips onto the fascia below it year round, not just when it rains.
A seamless gutter is formed from a coil of aluminum right at your house with a portable machine, cut to the exact length of each roofline. The only seams left are at the outside and inside corners and where an end cap goes on, so there are far fewer places for ice to start a failure.
Sizing for the roof, not a standard size
Fargo roofs vary more than people expect. A steep ranch roof pushes water off fast in a heavy thunderstorm, and a lower pitched roof lets snow sit and melt slowly. We size the gutter and the downspout count to the actual roof area draining into each run, not to whatever size the last owner happened to have installed.
A gutter that is undersized for the roof above it overflows in a hard rain even when it is perfectly clean, and no amount of cleaning fixes that. Getting the size right the first time is cheaper than replacing an undersized gutter twice.
Aluminum, and why we do not push steel or copper here
Aluminum is the standard material for seamless gutter in this climate, and for good reason. It does not rust, it takes the coil-forming process cleanly, and it flexes slightly with temperature swings instead of cracking. Steel holds up to hail better but rusts at the cut edges over time, and copper costs far more than the difference in performance justifies for most houses here.
We use a heavier gauge aluminum than the thinnest stock on the market, because a gutter that dents under a ladder or a light hail event needs replacing sooner than it should.
Installation and the hangers behind it
The gutter itself only lasts as long as what it is hung on. We use hidden hangers screwed into solid fascia at a spacing tight enough to hold a full gutter of slush during the spring melt, not the wide spacing that saves a box of screws but sags within a few seasons. Where the fascia underneath has already gone soft, we replace it before hanging new gutter on it, because hanging a new gutter on rotten wood just delays the same repair.
Every run gets pitched toward the downspouts so water actually moves instead of standing, and every downspout gets sized and placed to keep water away from the foundation rather than dumping it against the house.