It’s all basically the same type of systems, it just varies as where they pull/send to. The vertical bore style is just straight down instead of loops in your backyard for the installations where there isn’t much yard to work with. It takes more specialized equipment because you’re drilling rather than just burying lines, hence most of the added costs.

Where I live it drops into the -30 to -40c degree temps and properly installed geothermal systems have no problems with it.