Get them and don't look back.
In general, Smartwool does a great job designing the fit of their socks, and getting a good merino wool blend that has all the properties we love with added durability.
These medium weights are perfect for just about everything. I bring them for coldweather camping, I've used them ice climbing, backpacking, and just in my slippers around the house. They breathe and wick well, they have great padding, and they fill your boot well when backpacking. I don't have the heavy hiking socks, but I couldn't see a use for them unless you were doing some really chilly backpacking or on a 10 day trip the required you to carry a heavy pack.