Like you said, Brian, it cost me near $5 a foot with the gutters, hangers, couplers, downspouts, etc. to put the vinyl gutters on my daughter's and my own aluminum patio awnings.
I went with standard run of the mill sectional brown vinyl 10 years ago and just took them down because I'm staining the house. They simply snap together. I need to replace a couple of hangers, but that's it. No ice damage, no leaks and they are not brittle with age.
I have 2 45' runs each with 4 downspouts and 2 35' runs with 2 downspouts. We don't have any trees near the house so they don't plug up. I've never seen a rainstorm they couldn't handle.
I saw these gutters on my mom's house in Sacramento, but haven't seen them anywhere else in the country, I like the fact that they completely cover the fascia board, in fact, you could use these in place of a facia board.
Oops, I'll have to resize first, back in a minute with the pic........
Seamless is the only way to go, IMHO. No leaks and they look nice. Make sure they use the hangers, some guys will just drive a spike in and bend it up a little, no good!. The guy covered mine with that small expanded metal type stuff and that has kept the leaves and other junk out for the past year.
Very important to route that water away from the house to keep freeze/thaw damage problems to a minimum. We routed all of ours into black corrugated pipe and dump it in the creek out back.