Pros for K-Style
Common. Most American homes use them and it is a socially acceptable practice, though you won’t be getting fashion points for them. They resemble the crown molding of a house and tend to be the default choice.
Cheap. Gutters don’t get any cheaper than this, except for just not installing gutters. Usually made of aluminum, they can be installed in just a few hours. However, don’t expect them to last more than a decade or two.
Cons of K-Style
High-Maintenance. Expect to clean them several times a year. The box shape doesn’t promote a healthy flow of water. They are prone to leaking and often need caulking to plug up holes that develop.
Short Lifespan. Aluminum and caulking are not materials that withstand extreme temperatures very well. Unless installed with copious amounts of brackets, they do not support near enough weight, especially if filled with ice. Seams galore, you will probably need to change them out before you could raise a child to adulthood.
Pros for European Style (Half Round)
Elegant. They are a home installation to be proud of and add value to the home, especially if they are copper. Why use any other metal than copper or zinc? While some may argue they may not be a fit for every home, well we agree. They would look dumb on a trailer.
Long Lifespan. If installed properly, they will more than likely outlast you. Unless you are expecting to live 120 years, copper or zinc half round gutters are durable, strong, and dependable. They require less maintenance given that their round design funnels water and debris effeciently.
Cons for European Style
More Expensive. You cannot install these for a few hundred bucks like a k-style system. If you are not wanting to make a lasting investment in a home, install something else. You pay for value.
Maybe Too Good. You don’t want the neighbors envying you and hating you for having such awesome gutters, don’t get half-round gutters. Just throw on some crappy K-style aluminum gutters and go buy a Pinto at the local dealership.