The Liberty REALLY pissed off the Jeep faithful when it was announced. They even had a petition to stop its production. You see, the Liberty is the first Jeep with independent suspension as opposed to the traditional Jeep live-axle. Despite what you might assume, independent suspension BLOWS for serious off-roading, and that's what Jeeps have always been known for.
That said, you might never take it off the pavement (like most SUV owners) so that might not matter to you. Just know that you'll be scorned by the mighty Jeep community.