The backgrounds are incredible and have a lot more detail than any other game, as well as huge hills, which makes the tracks feel less flat. (hardcoregaming101.net)
However, after pushing my body to the limits (thank you, huge hill at mile 7 of my last run) and feeling a well - deserved soreness for two days post-race, I realized that I have to challenge myself to see any results. (health.com)
The game's first DLC expansion, Blizzard Mountain, added snow to proceedings as well as a vastly different type of environment including plenty of huge hills to climb. (tiredoldhack.com)